air compressor motor trips breaker

Is Your Air Compressor Tripping the Breaker: Fix it today

There are two reasons an air compressor can trip a breaker, electrical and mechanical. Most commonly, the motor is pulling too much amperage but before diving into the electrical circuit. Inspect for mechanical issues, such as the pump being stiff or locked up. Inspect bleeder or loader valve. I run into this occasionally, I hate myself when I spend two hours testing circuits, and it should have been a fifteen-minute job replacing a bleed-off valve.

Safety first: safety glasses unplug the compressor. Visually inspect the compressor and surrounding area for obstructions to the mechanical parts of the compressor, such as pulleys, belts, pump, and the motor.

Before You Can Repair Your Breaker concern, let us save you some time by asking a few qualifying questions.

This is the first time plugging in this compressor, and the breaker tripped while running? a) my compressor is new b) my compressor is not new

my new air compressor trips breaker

The most common reason I find circuit breakers tripping with new compressors is too much load from combined amperage draw from multiple devices and tools on one circuit.

Sometimes on new compressors, the easiest way to cure this concern would be to move the compressor to a dedicated circuit large enough to handle the load. Moving the compressor may also identify a week breaker. If the breaker trips on one 15 amp breaker but not the other, The tripped one may be old and worn. I would recommend replacing that worn breaker and move the compressor back to its original location.

STILL, TRIPPING BREAKER?

Your air compressor is tripping the breaker due to untenable current demands that exceed the breaker’s capacity. Several factors can cause your compressor to pull too much power, but we will not waste time testing the compressor. If we determine it is the compressor, It’s new; bring it back.

Before resetting the breaker, find the amp rating on the compressor, be sure that the breaker is large enough to handle all the appliances and tools on that circuit. Take this time to unplug all other devices or tools that may be causing a draw on that circuit. Inspect the outlet that the compressor is now using. Is it lose, or has any signs of overheating? Replace the outlet or repair before going on to the next step.

How to test an unloader valve on an air compressor

To see if a failed unloader valve is the root of the problem, take the following steps:

Unplug your air compressor
Open the tank drain and let all pressurized air escape out of the tank
Plug the air compressor back in
Turn the air compressor switch to “ON,” restarting your air compressor. If the compressor starts, let the system fill.
if the compressor still will not start inspect the pump.
Once the compressor turns off, bleed some air until the motor starts. Replace the valve if the breaker trips while attempting to turn on with a full tank. The cause was the valve not releasing pressure from the cylinder head.

Inspecting an air compressors pump for mechanical concerns

To see if a failed pump is the root of the problem, take the following steps:

unplug the compressor
remove the cover plate or belt guard
turn the pump by hand it should spin freely

If the pump is locked or hard to turn, It time to replace the pump

If the pump turns freely its time to test the electrical circuit.

Disclaimer: Self-diagnosing air compressor concerns may not be a simple problem. If you are not familiar with electric motors or circuitry, then you may need to take your air compressor into a shop to have a load test performed and diagnosed. Performing electrical tests is hazardous and should only be performed by a professional.

Measuring the amps that your air compressor produces while in use can be done one of three ways at the breaker box, exposing the wires at the compressor or using a splitter between the outlet and the cord of the compressor.

Click the link below to skip you down the page that best fits your situation:

My compressor is:

220volt single-phase or 220volt three -phase

How to Measure amperage on an air compressor. 110-volt A/C

Note: The compressor should be almost full of air to represent a heavier load on the motor on start and run.

plugging in a splitter into the outlet then plugging the compressor’s cord into the splitter is much like using an extension cord is the easiest way to test amperage.

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measuring the amperage at the breaker box,

Safety glasses! Open the breaker box and turn off the main breaker,

reset the breaker to the compressor and then shut it off, remove the panel to expose the wires and breakers

place amp meter around the load wire, let some air out of the compressor so when you flip the breaker, the compressor turns on.

Watch the meter at start-up and while running.

Was the amperage on start-up and running lower than that of the manufacturer specifications?

2.measuring the amperage draw with an outlet splitter or inline wattage meter. If You have this splitter, it makes life a whole lot simpler. Unplug the air compressor, plug the splitter into the wall plug in the compressor to the splitter. Clip your meter on the splitter. You are ready to start the air compressor. measure the amps at start-up and while running

3.Measuring the amperage draw on the air compressor is my last option. The only reason I sometimes measure amperage this way is I suspect the capacitor, and a quick visual inspection may reveal it needs replacing. All air compressors are different, and the manufacturer uses as little wire as possible, making it sometimes challenging to expose and separate wires. Once you have gotten a location to clamp the meter. Start the compressor and watch the amps at start-up and while running.

Was the amperage on start-up and running lower than that of the manufacturer specifications?

How to measure amperage on an air compressor. 220-volt A/C

Safety first! Unplug or turn off the breaker, test to make sure power is off. Inspect all wire connections on the compressor. Removing cover plates to expose the wires will provide a place to use your amp meter.

I always recommend measuring 220 Amperage at the Breaker box. All connections, including the ones at the breaker, need an inspection.

220-volt has one common or neutral lead and two load wires measuring 110 volts. It is also possible it will have a ground wire. Place the amp meter around one of the two load wires. Start the compressor and let it run until it shuts off.

Note the amperage. Move your meter to the second load wire.

Bleed air from the system until the compressor starts and repeat the procedure.

If you are dealing with a new compressor and producing more amps than the manufacturer’s specifications, return it to the store. Brandnew compressor failure is more common than you would think.

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(yes)If you Verified that the amperage draw is lower than the factory specifications and that of the breaker. The tripped breaker may be old and worn. Is it Possible to move the compressor to another circuit with the same amperage rating? Cycle the compressor on that circuit if there is no problem with that breaker. I would recommend replacing the worn breaker.

(no) A faulty capacitor is the most common cause for compressor tripping a breaker. Some compressors have two capacitors, and some have only one.

How to test an air compressor capacitor. with video

Safety First: Wear safety glasses disconnect power, and make sure power is not present.

Remove the cover to the capacitors. One capacitor will be the start capacitor. The other will be the run capacitor. Ratings and percentages are printed on the side of all capacitors. If it is not legible, there will be no way to test the capacitor. I usually replace capacitors that look distorted in any way, and capacitors are cheap enough that the cost is negligible compared to labor or a comeback.

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Caution: A Capacitor can store a deadly D/C discharge!

With an isolated Scew driver, touch the top leads together on the capacitors. Discharging them eliminates the chance for shock.

Now that it is safe to handle the capacitors, remove them and look at the side of the capacitor; take note of the micro-farad range. The format will read something like(540-630µf) or (64µf + – 6%) but not those exact numbers, and This micro-farad range is the tolerance the motor needs to start and run under random loads generated by the compressor. In the first example (540-630µf), when testing the capacitors, the micro-farad range should fall between those readings. In the second example (64µf + – 6%), you must first do some math. 64×0.06=3.84 round up to the next highest round number equals 4.0 64 minus four equals 60 and 64 plus 4 equals 68

in this example, the capacitors range is between 60µf and 68µf.

Set your meter to this symbol -)|- or the µf. Connect the leads and measure the micro-farads. If the reading falls between the variance, the capacitor is good. In this example, the reading reads 61.2 µf the capacitor is within tolerance. And we would move on to the next step or the next capacitor. Replace the capacitor if it is out of range.

Is your air compressor the cause of your breaker tripping #weakbreaker

If you plugged the compressor into another outlet and the breaker did not trip, or you measured the amperage draw during use and the beakers ratings are above that witch the compressor is drawing, chances are the breaker is weak or there is a loose wire in that circuit. inspect the circuit for loose wires and replace the weak breaker.

10 Reasons Why Your Air Compressor Keeps Tripping the Breaker

Few things are as frustrating as trying to use your air compressor only to have your circuit breaker trip – especially if it happens over and over again. To make matters worse, there are numerous possible causes, many of which can be difficult to diagnose. So this article will cover the many possible reasons your air compressor is tripping your circuit breaker, how to diagnose them, and what to do about them.

A word on circuit breakers, immediate or delayed breaker trip, reason #1 your circuit is overloaded, reason #2 faulty circuit breaker or wiring issue, reason #3 short-circuit/failed capacitor/loose wiring in compressor, reason #4 dirty air filter or cooling components, reason #5 low oil/too much oil, reason #6 extension cord/power strip, reason #7 clogged cylinder, reason #8 damaged/improperly tensioned belt, reason #9 failed unloader valve or check valve, reason #10 faulty pressure switch, air compressor keeps tripping breaker conclusion, air compressor tripping breaker faq’s.

A circuit breaker is a switch designed to protect an electrical circuit (and the devices drawing power from it) from damage due to faults, shorts, or excessive current. They are located in your electrical distribution board (aka breaker box). When an electrical anomaly or overload is detected, the breaker will automatically “trip,” cutting off power to the circuit.

This gives you some idea of what’s going on when your air compressor trips the breaker – it’s usually due to an overload or electrical fault of some kind.

The first thing to keep in mind when troubleshooting a circuit breaker trip is when the breaker trips. Does it happen as soon as you turn it on or after it’s been running for a few seconds or more? The answer may point you in the direction of the root cause. That being said, some issues may cause either an immediate or delayed trip.

With that in mind, we’ll examine the possible causes in each scenario separately.

Air Compressor Trips The Breaker As Soon As It Starts

First, let’s look at what might cause your air compressor to trip the breaker immediately on startup. ( Note: this means when you initially turn it on, not when the pump kicks back on automatically during use – we’ll explore that scenario in the next section. )

Before looking at the air compressor itself, it’s best to rule out issues with your circuit. One of the most common causes of a tripped circuit breaker is a simple overload of the circuit. If you have multiple devices plugged into the same circuit, turning on your air compressor may simply put it over the edge – air compressors tend to draw a lot of power when the motor starts up. This issue may not always occur immediately on startup and may be accompanied by flickering/dimming lights.

Solution: Find out what other appliances or lights are on the same circuit and try unplugging other devices or plugging your compressor into another circuit with fewer (or no) other devices or lights connected to it – the closer to the breaker box, the better. If this solves the problem, the likely cause was an overloaded circuit.

The issue may also be with the breaker itself or a wiring issue somewhere else in the circuit. Breakers can wear out over time, so if you have very old breakers, this may be the issue. When a circuit breaker trips it can be from a loose or damaged wire, whether in the breaker box, outlet, or compressor power cord – or anywhere in between. A damaged extension cord may also be to blame (more on extension cords later).

Solution: Inspect visible cords for damage. If using an extension cord, try plugging directly into the wall instead; if the compressor power cord is damaged, you may need to take it to a professional for repairs. Test the circuit for continuity using a multimeter, or replace the breaker. This can be dangerous, so if you’re not comfortable and familiar with electrical work, don’t hesitate to hire an electrician.

If the circuits are fine and aren’t being overloaded, you may have a short in your compressor. This can be caused by a loose electrical connection, failed capacitor , or shorted motor windings (the coiled copper wires on a motor). Any of these issues can create an overdraw of amps, which will cause the breaker to trip.

Solution: With the compressor turned off and unplugged, check all electrical connections in the compressor head and tighten if necessary (your user manual should have instructions on how to do this). If this doesn’t solve the problem, you’ll have to test the motor windings and capacitor(s) to ensure they’re working properly. Again, unless you have experience with this, you’re probably better off taking it to a motor/compressor repair specialist to have this done.

In some cases, the motor or pump may simply be on its last leg, particularly if it’s very old. If so, you’ll likely be better off replacing the whole compressor.

Air Compressor Trips Breaker After Running for a Few Seconds (Or Longer)

It’s typically more common for an air compressor to trip the breaker after running for a short time or as the motor kicks on a second time to maintain pressure in the air tank. Let’s look at the possible causes of this.

If your compressor’s air intake filter is clogged with dirt and dust, it can strain the motor, causing it to draw more amperage than normal. If this excess power draw exceeds the breaker’s capacity, it will trip the breaker. Similarly, if the cooling fan intake grate or any other air pathways are clogged with gunk, the motor may overheat and cause the breaker to trip.

Solution: Clean or replace the air intake filter. Clean any other air pathways or cooling apparatus such as intake vents and cooling fins (compressed air and a microfiber cloth work well). Run the compressor again to make sure the problem is solved.

If your compressor is oil-lubricated, make sure it has the correct amount of oil in it. Too much or not enough oil can both cause the pump to struggle and overdraw power, resulting in our air compressor tripping the breaker

Solution: Check the oil level to ensure that it’s right where it should be according to the instructions in your user manual. Add or drain oil accordingly and try to run it again. If oil has entered your air chamber you may need to wait a day or so to let it drain back down into the sump.

Air compressors and extension cords don’t get along very well. Most extension cords aren’t rated for the amperage draw of compressor motors, which means the motor will be underpowered. This can cause the motor to overheat and trip the breaker. The same goes for power strips – and if several devices are plugging into the same strip, it can overload the circuit.

Solution: Plug the air compressor directly into a wall outlet or use an extension cord that’s rated for your compressor’s amperage (and the shorter, the better). In general, it’s always better to use a longer air hose instead of an extension cord.

If one or more of the pump cylinders has become contaminated with grit or rust, the piston(s) may not be moving freely, which can result in overheating or overdrawing of power. This can also occur with rotary screw-style compressors.

Solution: If possible, try to crank the motor drive by hand (with the unit unplugged). If it’s stiff or stubborn, the issue may be a clogged or corroded cylinder or mechanical element inside the pump. You’ll likely need to have this repaired by a professional. In some cases, you may need to replace the pump, compressor head, or entire compressor.

If your compressor uses a belt drive system, the issue may simply be that the belt is worn out or not tensioned correctly and is putting undue strain on the motor.

Solution: Inspect the belt for wear and tear; check for proper tension. Replace or re-tension the belt per your user manual’s instructions.

An unloader valve is a crucial component of an air compressor. When the tank reaches its pressure limit and the pump stops, the unloader valve releases any air trapped in the air chamber above the piston. If this valve malfunctions, the air will remain trapped and increase the load on the motor when it restarts to maintain tank pressure. This increased load can cause a spike in amperage draw and trip the breaker.

Similarly, compressors have a check valve that prevents air in the tank from flowing back into the air chamber. If this malfunctions (stays open), air from the tank will reverse course into the air chamber and overload the piston – again, possibly causing a tripped breaker.

Solution: Unplug your compressor and drain all of the air out of the tank. Then, plug it back in and turn it on with an empty tank. If the breaker trips while the tank is filling, it’s likely the check valve. If it doesn’t trip until the pump kicks on a second time (to maintain tank pressure), it’s most likely the unloader valve. In either case, the solution is to replace the valve in question.

If the breaker trips as the pump restarts to maintain tank pressure, another possible cause is a faulty pressure switch. When the tank is drained to a certain level, the pressure switch sends a signal to the motor, telling it to kick back on and pump more air into the tank.

If the contact terminals inside the pressure switch are worn or loose, it may create a short-circuit that trips the breaker.

Solution: Unplug the compressor and drain the air tank completely. Remove the cover on the pressure switch to expose its internal components (be very careful – you’ll be exposing live contact terminals that can shock you). Plug the compressor back in and turn it on, keeping an eye on the terminals. If you see any arcing or sparks, you have a faulty pressure switch. In this case, simply replace the pressure switch.

As you can see, there are numerous reasons your air compressor might be tripping the breaker. But with the help of this guide, you should be able to solve the problem with a little investigation and experimentation. However, always follow the safety precautions detailed in your compressor’s user manual and never attempt tests or repairs that you’re not comfortable with – especially where electrical components are concerned.

Can a bad compressor trip a breaker?

A bad compressor can trip your breaker. One that has trouble starting will pull more electricity than normal. And sometimes more than the breaker can handle. Which in turn would trip your breaker.

What is a common problem fault on an air compressor?

A few of the most common problems on air compressors are broken parts, oil leaks and air leaks. Each of these may cause your compressor to stop running or to not be able to start.

How do I stop my air compressor from tripping the breaker?

The first thing to check when trying to stop your air compressor from tripping the breaker is if the circuit you are using has enough amps to handle the compressor. If it does not have enough, move it to a dedicated circuit large enough to handle the draw your compressor is pulling.

Can An Air Compressor Be Laid Down or Stored on Its Side?

Air compressor types compared (pancake, hotdog, twin stack, vertical).

Why Does My Air Compressor Keep Tripping The Breaker

Are you having trouble with your air compressor tripping the breaker? This problem can be extremely annoying, leading to disruption and loss of power in the middle of a project. Fortunately, there are typically many solutions that could help you avoid this issue all together.

In this blog post, we’ll discuss the 10 most common reasons why air compressor trips the circuit breaker when operating, along with potential solutions to address each cause, so that you can get back up and running quickly and efficiently.

Five-minute read

Why Does My Air Compressor Keep Tripping The Breaker?

Why Does My Air Compressor Keep Tripping The Breaker

10. Low Refrigerant Level of an Air Conditioner Compressor:

Air compressor tripping breaker:.

If your air compressor is tripping the breaker, it could be due to a variety of reasons. First, check if the voltage and amperage given from your power outlet match with the requirements on your air compressor’s nameplate. If not, you’ll need to adjust or replace the breaker with one that matches those requirements.

The power supply may also be overloaded, causing the breaker to trip. Check if you’re connecting too many items to the same circuit and remove any unnecessary items from the outlet. If your air compressor has an internal motor overload protector, make sure it is properly adjusted for your voltage and amperage requirements.

In some cases, the air compressor itself could be malfunctioning or failing components in its electrical system can cause a false “overload” situation that will trip the breaker. You should check for any loose wires, broken switches and frayed cords, as well as worn brushes on the motor of your compressor.

Finally, inspect all hoses connected to the air compressor to ensure they are intact, not kinked, and the couplings are secure.

If you still can’t identify the source of your problem, you should contact a professionally trained service technician to inspect and repair your air compressor. Taking these steps will help ensure that your air compressor runs safely and reliably for years to come.

10 Possible Factors & How To Solve Them:

1. Overloading of the Circuit

2. Poor Insulation on the Air Compressor

3. Dust or Dirt in the Motor

4. Faulty Electrical Wiring

5. Improperly Sized Circuit Breaker

6. Excessive Voltage Drop

7. Poor Engine Performance

8. Faulty Pressure Switch

9. Leak in Compressor Line

10. Low Refrigerant Level of an Air Conditioner Compressor

Now lets discuss these factors one by one in detail and how to solve them.

1. Overloading of the Circuit:

If you’re using too many appliances on one circuit, it can overload that circuit and cause the breaker to trip. The solution is simple, just move some of your appliances onto another circuit.

Move some appliances to another circuit.

2. Poor Insulation on the Air Compressor:

If your air compressor has poor insulation, it can heat up more quickly and trip the breaker when it reaches a higher temperature than expected. The solution is to replace any worn or damaged parts with high quality products that are properly insulated for maximum protection against overheating.

Replace any worn or damaged parts with high quality, well-insulated products.

3. Dust or Dirt in the Motor:

A buildup of dust and dirt from frequent operation can lead to a decrease in performance and cause the breaker to trip, so be sure to clean out your air compressor regularly.

Clean out your air compressor regularly.

4. Faulty Electrical Wiring:

Faulty electrical wiring can cause the air compressor to draw more electricity than it needs and trip the circuit breaker. To fix this problem, inspect all of your wiring for any signs of damage and replace any faulty parts as needed.

Inspect all wiring for any signs of damage and replace any faulty parts as needed.

5. Improperly Sized Circuit Breaker:

If you have a mismatched circuit breaker, it won’t be able to handle the amount of power that your air compressor needs and will trip off when the current exceeds its rating. The solution is to install the right size circuit breaker for your application.

Install the right size circuit breaker for your application.

6. Excessive Voltage Drop:

Voltage drop is an issue where there is too much resistance in the wiring, which will cause the power to be weaker and potentially trip the breaker. To resolve this issue, inspect your wiring and make sure that all of your connections are secure and up-to-date.

Inspect wiring and make sure all connections are secure and up-to-date.

7. Poor Engine Performance:

If your air compressor’s engine is not performing well, it can draw too much current and trip the breaker. To fix this problem, check your engine and make sure that all parts are in working order; if necessary you can replace any faulty components with new ones.

Check engine and make sure all parts are in working order; replace any faulty components with new ones if necessary.

8. Faulty Pressure Switch:

If your pressure switch is faulty or worn out, it won’t be able to accurately detect pressure changes and may cause the breaker to trip unnecessarily. The solution is to replace the pressure switch with a new one.

Replace the pressure switch with a new one.

9. Leak in Compressor Line:

If there is an air leak anywhere within the compressor’s line, this can cause the unit to struggle to maintain enough pressure and thus increase strain on its motor, leading it to trip the breaker. To fix this issue, check for any loose connections or worn-out hoses and replace them if necessary.

Check for any loose connections or worn-out hoses and replace them if necessary.

If you have an air conditioner compressor, it may be tripping the circuit breaker due to a low refrigerant level. To fix this problem, first check the refrigerant level; if it is below the recommended amount, top up with fresh refrigerant until it reaches the correct level.

Check refrigerant level and top up with fresh refrigerant if it is below the recommended amount.

If your air compressor is tripping the circuit breaker, any of these 10 causes could be to blame. By following these solutions, you can get back up and running quickly and efficiently. Remember, if the problem persists or if the circuit breaker continues to trip, be sure to seek professional help.

Conclusion:

While all of these potential solutions may help you avoid breaker trips in the future, if you continue to have trouble with your air compressor tripping the circuit breaker, it’s best to consult a professional. Often times, there is an underlying issue that is causing this problem, and a trained technician will be able to quickly diagnose and fix the issue, so that you can get back to using your air compressor without interruption.

Why Does My Air Compressor Keep Tripping the Breaker?

Written by Edwin Jones / Fact checked by Andrew Wright

Does your air compressor circuit breaker trip every time you turn it on? Do you want to know how to stop air compressor from tripping breaker?

There are many factors why your air compressor trips your breaker. Additionally, each factor that affects the air compressor also has different types of solutions. So to fix this, you need to understand some of the problems it may encounter, thus causing the tripping.

Read on to find out the answer to “why does my air compressor keep tripping the breaker?” and how you can troubleshoot it.

Table of Contents

1. Shorted Air Compressor

2. damaged or shorted wire, 3. high power draw during start-up, 4. clogged condenser coil, 5. not enough or too much freon, 6. damaged condenser motor, 7. damaged contactor, 8. dirty air filter, 9. grounded disconnect switch, 10. faulty circuit breaker, possible factors.

Troubleshooting an air conditioning compressor can be challenging to do so. You need to trace the source of the problem, which is mainly under the purview of professionals. However, even DIYers can learn a thing or two to do their own checks.

Safety first: Before starting with your inspection, take precautions, especially when working with electricity. It’s best to disconnect the airconditioner’s main power before doing anything.

To give you an idea about the factors that affect your air conditioning compressor and breaker, these are some common problems that you might encounter. There are also included tips that can help you repair it quickly and easily. But if you’re not sure of what you’re doing, leave it to the professionals!

The most common reason for circuit breaker trips is a shorted air compressor. Sometimes, the air compressor trips breaker immediately, but sometimes it makes a noise for a moment before it trips its dedicated breaker.

Check the line and terminal of the air compressor with your multimeter. However, to test if the real short is your compressor, disconnect it from the circuit then turn on the affected breaker. If the breaker does not trip, then the compressor is the problem. In that case, you need to find a professional to look at it.

Furthermore, here is a detailed guide about breaker size for air compressors if you needed!

There is the possibility that the wire insulation connecting the air compressor to the breaker might be damaged. It could be because of animal bites, like mice, or simply due to aging. If this happens, it may short if it accidentally contacts other cables.

You should check the air compressor’s cable, starting from the disconnect switch up to the circuit breaker panel. If you find a damaged wire, repair it using wire and terminal connectors. You can find a good pair in the top-rated wire connector article so you can find a suitable wire connector to help you with your repair.

If your air compressor tripping breaker on startup, or if your lights dim or fluctuate for a few seconds every time you turn it on, it means that it has a high power draw. This high power draw might exceed your circuit breaker’s capacity, leading to a trip.

The best thing you can do about this problem is install a hard start kit containing a relay and a hard start capacitor. It can help drop the amp requirement by up to 50% for every startup. Check this guide to know how many amps an air compressor uses!

A clogged condenser coil can also cause an increase in amp requirements. If the air that goes to the air compressor is blocked by too much dirt, the fan will have to work harder, increasing its power draw.

To clean it, spray the coil with water using a water hose from the inside out. However, be careful while doing this, as too much force from your pressurized hose might damage the coils.

Freon levels may also be a reason your circuit breaker trips. When the freon in your air compressor does not match the manufacturer’s requirement, this can cause the unit to malfunction, therefore causing the trip. Unfortunately, you need a technician to check it and see if it’s the actual cause of your issues.

If your air compressor runs slow then trips breaker, check your condenser fan if it’s stuck or doesn’t rotate as fast. That could mean your condenser motor is damaged. This is because the fan draws a lot of power to cool your unit, which it doesn’t do well because of the damage.

A contactor is the one that controls the voltage of your air compressor. If the voltage is uneven for both terminals, it may result in tripping your circuit breaker. Test the voltage with a multimeter to see if you get voltage fluctuations. However, be careful during your testing as you’re dealing with live power.

A dirty air filter can also cause breaker trips. Like a dirty condenser coil, a dirty air filter can reduce airflow, thus requiring the fan to work harder.

Furthermore, the air filter prevents dirt from coming into the air pump. If it’s too dirty, it could fail and let contaminants into the pump itself, leading to expensive repairs. Change your air filter when you see that it is dirty.

A grounded disconnect switch may lead to a short circuit. It is also dangerous as it’s typically attached to the metal casing, thereby increasing the risk of electrocution. Regularly check the disconnect switch terminals and replace them immediately if you see any damage, like scorch marks.

If you’ve checked all the factors above and your compressor keeps tripping breaker, you may have a faulty circuit breaker. Call a professional electrician to check if your breaker is defective.

However, if you also see some scorch marks in your circuit breaker, immediately replace your breaker before it gets worse.

Note: Before troubleshooting your equipment, turn off your circuit breaker or pull out your disconnect switch. It ensures that no current flows into your air compressor line and keeps you safe from electrocution. You could also watch this video by Word of Advice TV so you can have a better idea of how to troubleshoot your air compressor.

All of the factors discussed above are some of the most common reasons air compressors cause breaker trips. If you’re experiencing the same problem, you can go through them one by one and see which one affects your unit. Still, if you’re unsure of what you’re doing, it’s best to call a professional electrician.

That way, you and your property can remain safe.

So, did you find the answer to why does my air compressor keep tripping the breaker? If you have additional questions regarding your air compressor unit, leave them in the comments section below.

I am Edwin Jones, in charge of designing content for Galvinpower. I aspire to use my experiences in marketing to create reliable and necessary information to help our readers. It has been fun to work with Andrew and apply his incredible knowledge to our content.

Troubleshooting Air Compressor: Keeps Tripping Reset & Blowing Fuses

Air Compressor Keeps Tripping on Reset & Blowing Fuses

How to Troubleshoot an Air Compressor That Keeps Tripping on Reset & Blowing Fuses

So it’s a regular day in the shop just like any other, you’ve got your air compressor tank filled up with air, you get to use your air tool. However, this time it’s a little bit different. The pressure in your air compressor tank starts dropping, and the compressor starts tripping on reset. You might even notice that your fuse blows altogether when you try to restart your air compressor.

Naturally, this may leave you in a panic as thoughts flood your mind. What’s going on with my compressor? Why is it acting up when I take care of it as I should? Is this the end of my air compressor?

Well, don’t get yourself into too much panic before understanding what’s going on. In this article, let’s take a look at how to troubleshoot an air compressor if it keeps on tripping on the reset or blowing fuses. Lucky for you, this isn’t necessarily the end of your air compressor, and there’s usually a good reason as to why it’s acting up all of a sudden.

So what’s happening with my air compressor?

The typical cause for all this is a shortage in the internal flow of processes in your air compressor that makes it work as you’ve come to expect. Normally, once your air compressor’s tank fully drains all the way to a level of pressure cut, your air compressor system would start and run normally until the tank’s pressure reaches the cut setting, which is when the compressor would typically stop.

Once your compressor reaches the pressure cut setting, your air compressor’s pressure switch contacts start to close, creating a complete circuit through which power can then flow through to reach the circuit responsible for the motor start.

However, if your motor is unable to start, it still continues to draw on power from the power source and can even pull enough power (amperage) to go beyond the maximum capacity of your breaker. In turn, this results in your compressor tripping the breaker when you perform the next restart. This, my friends, is why this happens with your system.

Troubleshooting Tips

Is your air compressor plugged into an extension cord or power bar?

If you’re plugging your compressor into one of the above, this may be the culprit. Many home purpose extension cords and power bars are well-known for limiting or governing power, rather than allowing the full wattage to be utilized by your compressor. This can lead to a decreased level of power supplied to the motor, which results in overheating that can contribute to the trip happening in the breaker.

Rather than using an extension cord, plug your air compressor straight into a wall power outlet. A power outlet of 20 amps or more is even better.

Is your unloader valve working?

Another common culprit that may cause this malfunction is your unloader valve not working. In some cases, if the unloader valve fails, some of the air compressed in the tank may get trapped over the cylinder piston. That air then adds to the overall load on the motor, which may potentially force the motor to pull too much power, thus blowing the fuse or popping the breaker.

Did your pressure switch fail?

Although this is much less likely to be the cause, it is still a possibility that a pressure switch may have shorted out, causing your compressor to trip the breaker on reset. To check if this is the cause of your issue, unplug your compressor, drain the tank, take off the cover, restart/reset the breaker system, and then watch for any signs of sparking or arcing. If so, this could be an indication that your pressure switch is the culprit.

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Air Compressor Keeps Tripping Reset? (We Have a Fix!)

There is nothing quite as frustrating as your equipment quitting while you’re trying to complete a project. Have you ever been working and suddenly your air compressor trips to reset? Before calling it quits yourself and buying a new air compressor, there are a few things to check that might solve the problem.

If your air compressor keeps tripping reset, it’s doing so because it’s overheating. This might be because your power supply is not large enough to power the compressor. It might also be that the compressor is overheating from running for too long. Lastly, the centrifugal switch may not be functioning properly.

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A Reset Button’s Purpose

A reset button on an air compression is also known as a thermal cut or safety switch. It can be located on the end or the side of your compressor. In some cases, it’s located inside the wiring of the motor.

The reset button is there for your safety. Its main purpose is to automatically turn off the air compressor’s power when it overheats. If a compressor were to overheat without the presence of a reset button, the motor would be damaged. If your air compressor is tripping, it’s because it’s too hot.

Air Compressors

Using a gas engine or an electric motor as its source of power, an air compressor continuously sucks volumes of air from the atmosphere. It then compresses or squeezes that air into a tight space in order to make the volume smaller and increase its pressure . The high-pressure air is moved to a receiving tank which then powers the equipment.

Three Basic Types

The three basic types of air compressors are as follows:

A reciprocating compressor has a cylinder with a piston inside which squeezes the air.
A rotary screw compressor compresses the air with a spinning spiral screw of steadily diminishing volume.
A centrifugal compressor has an impeller that rotates. The impeller transfers momentum to the air which then compresses it.

Any one of these types of compressors may trip your reset button if the power supply isn’t large enough , the compressor has been running for too long, or the centrifugal switch is getting stuck.

Not Enough Power

If you’re powering your air compressor with an extension cord or power bar, therein lies your problem. The power bar or extension cord may be too small to allow the proper flow of power.

By restricting the power through a smaller wire, the compressor motor can’t get a sufficient amount. This causes the motor to overheat which causes the thermal cut out to shut it down.

What’s the Fix?

Make sure your compressor is plugged directly into the wall outlet. A power outlet of 20 amps or more is best.

Running the Compressor Too Long

A compressor duty cycle is the length of time pressurized air can be delivered by the compressor. Typically, a duty cycle is between 10-15 minutes. If you run the compressor longer than the duty cycle allows, the compressor will overheat and trip to reset.

It’s likely that you will need to use your air compressor for longer than 15 minutes at a time. If that’s the case, you’ll have to take breaks in between uses. Run it for 10 minutes, and then, let it sit for just as long before running it again. This allows the engine enough time to cool so it won’t overheat too quickly during your next use.

Sticking Centrifugal Switches

The majority of air compressors have what is called a centrifugal switch. The centrifugal force caused by a rotating shaft (usually a gas engine or electric motor) activates the centrifugal switch.

If you think of it in terms of a car, the centrifugal switch is like first gear. It energizes the start-up windings. Once the compressor motor reaches ¾ of its RPM, it switches gears from the motor windings to the run windings.

Over time, the centrifugal switch can shift out of adjustment, causing it to get stuck in one position. If the centrifugal switch gets stuck in the open position, the windings won’t shift properly. The start windings can’t withstand the heat of the compressor’s full RPM, which will cause the compressor to overheat.

Depending on your comfort level and knowledge of centrifugal switches, you can adjust it yourself or replace it.

First, you want to make sure the points on the contact plate are in the open position. If they’re not, bend the circular spring flat so the points are no longer in contact. If the points are welded shut, then the contact plate needs to be replaced.

If there is light pitting on the surface of the points, you can sand them gently with 400 grit sandpaper. Larger deformities will create an unusable condition, so the contact plate must be replaced.

Tripping the Circuit Breaker

Occasionally, the problem may be bigger than the compressor itself tripping. What happens if you reset your air compressor only to trip your circuit breaker? There are a few things you can check to troubleshoot this problem.

Unloader Valve

If the unloader valve isn’t working, it might be the cause of the compressor’s malfunction. Sometimes, some of the compressed air gets trapped over the cylinder piston. That air adds to the load on the motor, potentially forcing it to pull too much power. This can trip a breaker or blow a fuse.

To find out if this is the issue, shut off the tank and unplug it. Then, drain all of the air from the tank. This will relieve the pistons of any excess pressure, allowing the tank to start up normally.

It’s important to occasionally inspect and clean the unloader valve to avoid trapping air over the pistons. If the problem continues, the unloader valve may need to be replaced.

Pressure Switch

It’s a little more unlikely, but a possibility is that your pressure switch shorted out. To find out if this is the issue, take the following steps:

Unplug the compressor.
Drain the tank and take off the cover.
Restart the breaker system.
Watch for signs of sparking or arcing. If you notice this, the pressure switch is your problem.

After many uses, motors get worn. Loose capacitor wires, worn windings, and other general wear in a motor can cause breakers and fuses to blow. If you’ve been running your compressor on the same motor for many years, it’s time to change it out.

Check out our guide: What Size Breaker For An Air Compressor?

Are Your Air Compressor Vents and Filters Clear?

Sometimes, when your air compressor cannot correctly vent itself, it can cause the compressor to continually reset so that the device does not become overheated and damaged. While running the air compressor for an extended time can certainly cause the unit to overheat, clogged vents and filters can also make the compressor overheat even more.

When the air vents and filters are clogged, the machine has to work harder than normal to pull in air from the outside. When the pump and motor are overworked, they can trigger the reset switch. Be sure always to clean the vents and filters on your air compressor and ensure there is no debris, hair, dust, or lint interfering with the machine’s ability to pull in outside air. Part of your routine maintenance on your air compressor should consist of routinely cleaning the vents.

Is Your Air Compressor Properly Maintained?

Sometimes, poor maintenance can cause your air compressor to reset continually. This fact is because there may be a mechanical issue within the air compressor that is causing the reset switch to trip before the tank is full.

To ensure that your air compressor is well maintained, you’ll want to perform a routine inspection about every six months to ensure that all the fittings, valves, and gaskets are in good working order. If your air compressor is continually resetting, you may have an issue with a broken pressure valve or possibly a broken gasket. Changing the valve or the gasket will help the compressor reset only when needed and help it maintain appropriate pressure.

Summing It Up

The reset feature on an air compressor is very important for your safety as well as the compressor’s motor. When the compressor overheats, the reset button will automatically shut it down to avoid hazardous heat levels.

To avoid tripping your air compressor to reset, make sure you’re taking breaks while using it to allow the compressor’s motor to cool. Check that the unit is plugged directly into the wall so that enough power can flow to the compressor. Inspect the centrifugal switch to ensure that it’s working properly and not getting stuck in one position.

It can be frustrating when the air compressor keeps tripping in the middle of a project, but remember, it’s for your protection. Hopefully, one of these solutions will fix the problem so that you can get back to using your air compressor peacefully.

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Brigid Levi is a wife, mother, and freelance writer who enjoys a good DIY project and creating beautiful spaces within her home. From cleaning and organization hacks to home decor ideas, she loves helping people in their quest to turn a house into a home. Her hobbies include pretending to be Joanna Gaines while updating her home with her husband and performing in local theater productions.

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Expert Advice On Improving Your Home

Troubleshooting a Tripped Circuit Breaker

Author, Editor

Alora Bopray

Staff Writer

Alora Bopray is a digital content producer for the home warranty, HVAC, and plumbing categories at Today's Homeowner. She earned her bachelor's degree in psychology from the University of St. Scholastica and her master's degree from the University of Denver. Before becoming a writer for Today's Homeowner, Alora wrote as a freelance writer for dozens of home improvement clients and informed homeowners about the solar industry as a writer for EcoWatch. When she's not writing, Alora can be found planning her next DIY home improvement project or plotting her next novel.

Roxanne Downer

Roxanne Downer is a commerce editor at Today’s Homeowner, where she tackles everything from foundation repair to solar panel installation. She brings more than 15 years of writing and editing experience to bear in her meticulous approach to ensuring accurate, up-to-date, and engaging content. She’s previously edited for outlets including MSN, Architectural Digest, and Better Homes & Gardens. An alumna of the University of Pennsylvania, Roxanne is now an Oklahoma homeowner, DIY enthusiast, and the proud parent of a playful pug.

Expert Reviewer

Reviewed By

Laurie Engle

Expert Writer & Reviewer

Laurie Engle is a freelance writer who provides insights to homeowners on topics such as the home warranty industry, relocation issues, and real estate trends. As a licensed Realtor since 2001 Laurie has acquired extensive expertise in dealing with home warranty companies and navigating the intricacies of the real estate market. In addition to her commitment to helping clients with their home buying and selling needs, she maintains a sharp awareness of market dynamics, including property values, interest rates, and local regulations.

May 30, 2024

A tripped circuit breaker can be frustrating to deal with. When your circuit breaker keeps tripping, finding the culprit can be a challenge. If your air conditioner or heat pump unit is the culprit that caused a circuit overload in your home or office, there are a few possibilities to explore.

These circuit breakers, found in your electrical panel are safety devices that protect the electrical wiring from further damage and homeowners from electrical shocks. In this article I’ll talk about two common reasons for circuit breaker trips — earth leakage and overcurrent — and help you with troubleshooting this electrical current issue.

Tripped Circuit Breaker Due to Earth Leakage

The earth leakage circuit breaker (ELCB) that trips the electrical power to the house when a lightning strike happens can easily be restored. Switch the lever from the OFF position back to the ON position.

In the case of faulty air conditioner equipment, the ELCB may trip due to earth leakage. In this case, you will need to isolate the cause of the power outage or repair the equipment before the flow of electricity can be restored to the entire home.

Here are some of the most common reasons that cause the earth leakage circuit breaker to trip.

The motor wires in the compressor touch the metal enclosure of the compressor. The wires of the compressor motor may come off due to excessive vibration or faulty design.

Once these wires that are connected to the hot circuits touch the metal enclosure which is grounded, current flowing to the ground causes the ELCB to trip.

Disconnect the electrical service power and all the circuits to the terminal of the compressor. Use a multimeter and set the scale to measure resistance. Check the resistance between each of the terminals to the enclosure.

If the reading is close to zero, that means that the exposed wire closest to that terminal has touched the metal frame. Repair the fault or replace the compressor before the equipment can be operated again.

Similarly, if the fault is due to the compressor fan motor or indoor blower motor, disconnect the power and isolate the circuits to the motor. Check the resistance of each terminal to the casing (if metal). If it is close to zero, that means that the exposed wire is touching the casing, causing it to trip. Remove the motor for repair or replace with a new motor before the equipment can be operational again.

In circuits that have live, neutral, and earth wires bundled together, there is a possibility that the insulator of the wires breaks down (due to overheating, faults, under specs or inferior wires). This breakdown causes the live or neutral conductor to touch the earth conductor. This will cause the circuit breaker to trip. Troubleshooting this problem is more complicated as it involves electrical circuits and not particular components.

Tripped Circuit Breaker Due to Overcurrent

If the miniature circuit breaker (MCB) trips, the fault could be an overcurrent or short circuit. An issue with the air conditioner may cause this circuit breaker to trip after it has been running for a while. This issue will take more time to troubleshoot as the problem does not happen immediately. Here are the possible causes.

Disconnect the mains power before checking the connecting power from the mains to the equipment. For example, if there are 3 terminals that connect the power to the compressor, open up the housing and check the connection.

Look out for darkened or black spots on the terminal indicating that an overcurrent has occurred. A loose connection will cause arching, thus drawing excessive supply and damaging the wires and the parts that are connected to it.

Tighten the connection after removing and reconnecting the wire that has been damaged due to overheating.

A licensed electrician will usually be able to troubleshoot this problem by using a tong clamp ammeter to measure the current of that particular conductor.

If the compressor has a mechanical part that malfunctions causing it to lock, the current to operate will be a few times more than the normal operation. When this happens continuously, the possibility of over-current to happen will occur, causing the circuit breaker to eventually trip after a certain period of operation.

If the compressor or fan motor uses a 3-phase induction motor, a loss of one phase will cause overheating to occur when operating at full load. If the thermal overload protection does not trip, the circuit breaker will trip if the current exceeds its specification. A good design has a phase loss protector built into the circuit to prevent the motor from running in the first place.

Effectively troubleshoot a tripped circuit breaker with a methodical and safe approach. For earth leakage issues, identify the faulty components such as the compressor or fan motor, or issues like shorted wires. Isolate the equipment, perform resistance checks with a multimeter, and repair or replace faulty parts. For overcurrent problems, pay attention to loose wire connections, potential compressor lock, and phase loss in three-phase systems. Make sure all connections are secure and verify the mechanical integrity of the compressor to prevent recurrent trips in your electrical system.

Circuit breakers are vital for protecting electrical circuits from damage, preventing electrical fires and electrical shocks. Perform regular maintenance and make repairs promptly to avoid future problems with tripped breakers.

Electrical safety is a priority when addressing electrical issues. I recommend you contact a qualified licensed electrician to repair your main breaker issues. The expertise of a professional electrician guarantees protection from electrical fires, overloaded circuits, and prolongs the lifespan of your equipment.

Expert Writer & Reviewer

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Fix My Compressor

How To Fix Air Compressor That Keeps Tripping Reset Button

A very common problem with air compressors is the reset button tripping after a couple of minutes, or sometimes even ten or fifteen minutes of running time. This article will provide information on why this is consistently occurring and how to fix it.

Air compressor reset button, excessive use, mechanical issues, air leakages, oil leakages, power issues, sticking centrifugal switch, faqs (frequently asked questions).

An air compressor’s reset button, otherwise known as the thermal overload button or safety switch, is located on the end of the air compressor or on its side. In some cases, it may be located inside the wiring of the motor.

The reset button is there to provide the user with safety. Its main purpose is to automatically turn off the air compressor’s power when it overheats. If a compressor were to overheat without the presence of a reset button, the motor will become damaged and lead to serious problems down the line. If the button is tripping then the motor is already getting hot.

If your air compressor reset button keeps tripping, it’s probably because your air compressor is too hot. Isn’t it so frustrating when you have a fully loaded air tank and you begin operating the air tool, and as the pressure starts to build, the air compressor suddenly trips the circuit breaker and the reset switch is good for absolutely nothing? This page will help you fix these issues. For information on an air compressor tripping the breaker on the restart , visit our article here!

Air Compressor Reset Button Problems & Fixes

There are numerous certain reasons as to why the reset button keeps tripping on your air compressor. And these reasons are:

Excessive use
Mechanical issues
Air leakages
Oil leakages
Power issues

Now let’s take a look at these problems and how to fix them!

A very common problem for reset button tripping is due to excessive air compressor usage, or otherwise known as the compressor running too long. A reasonable running time for an air compressor is not greater than 10 or 15 minutes unless the compressor has a 100% duty cycle and states that it can run for longer.

Exceeding the duty cycle of the air compressor will lead to the overheating of the motor, and so, you should try to run the compressor for a smaller amount of time, say around 10 minutes, to give the air compressor time to cool down before starting its cycle again.

Duty cycle is very important and it works on the basis that if your compressor has a 50% duty cycle, then for every 10 minutes of work, you should then have 10 minutes of rest. You can find the duty cycle of your compressor in your user manual, and if you do not have this, contact the manufacturer directly to find out.

You should make sure that you have no mechanical issues like a broken pressure valve or damaged gasket. Any damaged parts may cause the compressor to take more time to fill the tank and so this may trip the reset switch before the air compressor is full.

Inspect the pressure valve, gasket, and other parts and replace them if necessary. This will go a long way in cost-savings, downtime further risks, and damages, and also stop your reset button from tripping so often.

It’s common for older air compressors to develop a tank check valve leak. If this happens, air will consistently bleed out of the compressors tank, even during the compressors work time. This will make the air compressor run for a far longer period of time to fill the tank – that’s if it ever reaches the cut out pressure.

Therefore, the motor will need to work harder and eventually overheat, causing the reset button to trip. This is also possible to occur on compressors that aren’t so old, and so it is important to conduct regular inspections on the valves to ensure no air is leaking from the system.

It’s possible that the valves on your air compressor are allowing oil to leak out of them. If this is the case, your air compressor will take a lot more time to fill the air tank and so the motor will overheat and trip the reset button. You should inspect all valves and connections for oil leakages and act swiftly if a leakage is found.

Finally, power issues are popular causes of the reset button tripping. You must try to avoid the use of a power extension or power bar and instead plug the air compressor directly into a wall socket. This is because air compressors require a high power supply, and the power extension or power bar may not be able to supply it effectively.

Too small of a power supply will lead to the motor overheating and the reset switch tripping!

The majority of air compressors have what a part called the centrifugal switch. The centrifugal switch is activated by a force caused by a rotating shaft (usually a gas engine or electric motor).

If you think about a car, the centrifugal switch is like first gear, It energizes the start-up windings. Once the compressor motor reaches about ¾ of its RPM, it switches gears from the start motor windings to the run windings.

Over time, the centrifugal switch can begin to shift out of adjustment, which causes it to get stuck in one position. If the centrifugal switch gets stuck in the open position, the windings will not shift properly. And if this happens, the start windings are unable to withstand the heat of the compressor’s full RPM, which will cause the compressor to overheat, tripping the reset button.

Therefore, it is imperative to conduct a check on the centrifugal switch and make sure it’s operating sufficiently. If you’re comfortable and have relative knowledge of centrifugal switches, you can adjust or replace it yourself. If not, seek professional help.

To adjust it, make sure the points on the contact plate of the switch are in open position. If they’re not, move the points so they are no longer in contact by bending the cicular spring flat. If these points are welded shut, replace the switch.

If there is light pitting on the surface of the points, you must sand them gently with sandpaper – 400 grit should do. Larger deformities will create an unusable condition, therefore the contact plate must be replaced.

Below is a useful YouTube video about an air compressor reset button!

There are numerous reasons why your air compressor is tripping the breaker. To prevent it from happening you must ensure that air filters and the cylinders are not clogged, you’ve plugged the compressor into a wall socket and not an extension cord, and that the circuit breaker, motor, pressure switch, capacitor, and unloader valve, are all working effectively and not fault. Replace any faulty parts immediately.

An air compressor’s reset button, or otherwise known as the safety switch or thermal overload button, is typically found on the end of the air compressor or on its side. In some cases though, it can be found inside the wiring of the motor.

There are multiple reasons why your air compressor is tripping, typically it will be down to something causing the motor to overheat, which trips the reset button. Anything like a leak, power or mechanical issues can cause the compressor to work for a longer period of time that’s it’s duty cycle states, this therefore leads to the motor working harder and overheating.

If you have any questions regarding the reset button tripping and how to fix it, please leave a comment below, with a photo if applicable, so that someone can help you!

By Ashley Pearce

As a passionate manufacturing and mechanical engineer, I've had my fair share of run ins with air compressors and compressed air systems. With over a decade of experience in the industry, I have both a fresh perspective and time-served hands and mind to help you with your compressor problems (along with our able community!)

I fixed mine from tripping the switch. I took a sledgehammer to the thing. What a waste of 3 grand and now I’m back using my little child’s air compressor. Sucks living off grid miles from help

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Campbell Hausfeld Air Compressor Trips Circuit Breaker – Solutions & Causes

Hey! This site is reader-supported and we earn commissions if you purchase products from retailers after clicking on a link from our site.

When a circuit breaker trips, the air compressor system shuts down, and work comes to a halt. When a Campbell Hausfeld air compressor trips a breaker, it’s a worrying issue, as you’ll no longer be able to use your air tools.

Therefore, it is important to understand why your Campbell Hausfeld air compressor is tripping the breaker. This article will provide you with all the relevant information, along with existing reader questions and responses.

Most common reasons your campbell hausfeld air compressor trips breaker, reader questions & responses.

Here is a list of the most common reasons your Campbell Hausfeld air compressor is tripping breaker:

Air filters – if they are dirty, you will likely need to replace them

Broken extension cords – are notorious for throttling power, and therefore you may be underpowering your compressor motor by using one.

Clogged cylinders – can hinder performance and trip breaker. You should inspect the cylinders (if your compressor has any).

Faulty circuit breaker – of course, it could be the circuit breaker that is faulty. Replace if necessary.

Faulty motor – the motor windings or any other electrical connections inside the motor may be shorting and this sudden flow of electricity pulls too many amps, tripping the breaker.

Failed capacitor – a failing capacitor can cause the breaker to trip, you should seek professional help to test this.

Failed unloader valve – When an unloader valve fails, compressed air becomes trapped over the cylinder piston. This adds to the load the compressor motor experiences on startup, tripping the breaker.

For more detailed information on why an air compressor circuit breaker trips , visit our guide!

5HP 120v Campbell Hausfeld Air Compressor Keeps Tripping Breaker

I have a 10-year-old Campbell Hausfeld 5HP 120v on a dedicated ckt. Has run flawlessly since new. I occasionally leave it turned on when I’m using it a lot, so I don’t have to wait for it to pump up. Now this Campbell Hausfeld compressor trips breaker.

Went out yesterday to pump up a tire and had no air pressure and the breaker was tripped.

Reset breaker, it ran for about 4 sec slowly, then tripped breaker again…repeatedly.

Removed drive belt and started again…motor ran normal speed, but then tripped breaker after 4 sec with no load. What do you think?

Dave, that’s a good one.

Good that you pulled the belt to check, as for me, that pretty much identifies the motor circuit as the source of the problem.

See this page on this site about checking your capacitors, as that would be the first thing I would check if my compressor was exhibiting your symptoms.

It turns out that I had a bad run capacitor in the motor. It was visibly swollen and shorted.

$27.50 for a new cap from my local motor shop and I’m back in business.

Thanks for all the suggestions.

Campbell Hausfeld Compressor Trips Breaker

But after using it for a while, the pressure goes down and it won’t turn back on, and trips the main fuse after it makes a starting sound, then a sound of air escaping coming from below the switch.

I have already replaced the broken fan and the rusted valve plate(kit) (pls. note..it’s not the check valve)

Edwin, the sound of air rushing from the pressure switch is, I suspect, that of the UNLOADER VALVE working.

The unloader valve opens when the pressure switch trips the power off, shutting off the compressor motor.

When the pressure switch trips on at low pressure cut in, that closes the pressure switch while the air compressor is running.

That your compressor dumps air again after trying to start suggests to me that it is your pressure switch that is failing, and when trying to start the air compressor, shorts the power, blowing the breaker, and tripping the pressure switch back off. I think!

If the pressure in the tank is below cut in, the compressor should start. When the tank pressure reaches cut out, the compressor should start. Both of these actions are initiated by the pressure switch reacting to the changing pressure in the tank.

If the pressure switch trips to off before the tank pressure reaches cut out, it is probably the pressure switch that’s at fault, and it’s shorting the circuit.

I have disconnected the motor from the compressor and direct-wired it to an outlet wired directly off the outside power supply.

What I am saying is this, the only wire between the motor and the power is the cord of about three feet long, a temporary outlet, and a breaker.

I plug it in and it blows the breaker! I took motor to an electric shop and the fellow there replaced the run capacitor it runs on his power supply?

I took it back home it blows the breaker immediately even with the new capacitor. Pretty frustrated now since the electric fellow can run without a problem. OK, so I am really scratching my head now?

If it runs at the repair shop, suggesting that the capacitor and the motor are fine, then the only variable is your power supply. You may have only a short cord to the motor, but what else is on the same circuit that is pulling power as your compressor motor is trying to run?

A slow motor 1/2 speed indicates the wrong motor voltage. Dual Voltage Motor, may be wired for high voltage 220 volts or may be 3 phase motor not single phase. Check motor plate for correct voltage and wiring. It is common for factories to ship motors wired to a higher voltage.

You must set to the voltage being used. Motor plate or spec sheet will state min. fusing required and maximum fuse allowed

Thanks, Bill, however that didn’t work either. It will run slower than usual like a half power then trip circuit breaker after about 5 seconds. It appears as though it simply can’t pull enough power but I am certain it has plenty for its rating. Thank you. What can I look at next?

Model WL611201aj Campbell Hausfeld Air Compressor Trips Circuit Breaker

I have a Campbell Hausfeld (6 hp 30 gallons) air compressor model WL611201aj that is about 14 years old.

When I turn it on the motor runs slowly and then trips the breaker.

It doesn’t matter if there is pressure or not in the tank. I have it plugged directly into a 120v 15 amp outlet. It has worked fine at the current location for some time. I recently switched outlets and the same result. If I use WL373001SJ Campbell Hausfeld Air Compressor Pump / Motor Kit replacement.

Will this fix the issue?

Vincent, if this was my Campbell Hausfeld air compressor, from the symptoms you describe, I would be checking out the start capacitor.

That would be quite a bit lower cost fix than the kit you refer to.

If you prefer, however, I do believe that the kit would resolve your compressor problem.

I agree with Bill, start capacitor would be where to start on this one. Buster

Can someone help me identify where the start capacitor is located on this model?

Vincent, the two “humps” sitting on the motor are the capacitors. One is the start cap, the other is the run cap.

I believe I have identified the start capacitor in this compressor. I have checked it according to the checking capacitors page listed here and it is bad. as well as split and leaking. The numbers listed are Aerovox c103237300423. 233-280mfd. 220vac. 60hz. The 220vac is confusing me. The compressor has run from a 110v 20 amp circuit for years. Anyhow, can someone tell me the best place to locate the correct capacitor?

I suspect the rating indicates that it’s good up to 220 VAC.

As to getting one, why not start with Aerovox themselves?

But when I removed the belt, the motor runs without tripping the circuit breaker. would this still be a starter capacitor problem? if so, please explain. thanks.

Your motor may have two capacitors or one that does both jobs – start and run.

If either is failing the motor will run hot if it starts.

The motor itself may be suspect.

One check to try and determine what has failed is to check the capacitors to take them out of the equation. See that page on this site for help in so doing.

By disconnecting the motor from any load, you reduce the inrush necessary to start the motor, and it runs. Add the belt, you increase the load, and the motor cannot start against it as, I suspect, the start capacitor cannot deliver the added power to get the motor going.

Thanks, bill! I replaced the starter capacitor and all is well again.

My Campbell Hausfeld wl506208aj trips breaker and quit working. Why?

Michael’s question:.

The motor starts then after about 5-seconds trips the circuit breaker.

The pressure gauge will be about 50psi.

This is a 120vac 14amp motor. I have moved it to other breakers including my new addition on the house which is a 20-amp circuit and nothing else on it. Any suggestions? Thank You.

Bill’s Response:

Michael, thanks for the info you provided. Knowing that you have checked the power supply helps.

Try this please. Unplug the compressor, open the tank drain, and allow all the air to escape. Close the drain and plug in / turn on, the compressor.

Does it start and run?

Response by Michael

Results from your suggestion

by: Michael

Hello, It is a dual tank model so each tank has a drain. I opened both drains. Nothing came out so I blew into the top tank drain and felt air coming out of the bottom tank drain.

After closing both drains I turned it on. The motor started and filled the tanks. The psi gauge filled to 145psi then stopped. The breaker did not trip. All seemed fine.

Then I attached my air ratchet and started using it. I noticed the psi gauge dropping then the motor started to hum but the compressor was not working. All I hear was the hum of the motor. After about 5-secs the breaker tripped. Thank you.

I think, based on what you have written, is that your unloader valve may not be functioning. Read the UNLOADER VALVE page for details.

Response by Michael:

About Unloader Valve

The unloader valve pages seem to describe the function of the valve. Should I be looking for pages to trouble shoot the valve? Not sure if I should be servicing the valve or replacing it. Thanks Again

Yes, but is the compressor unloader valve working? In other words, when the compressor stops, does the unloader valve dump the air over the piston, or not. If it does not, that is likely your problem. Then you can either try to fix the unloader, or more easily, replace it, though the latter will be more expensive as other components may have to be purchased along with the new unloader.

If you have any questions regarding your Campbell Hausfeld air compressor tripping breaker, please leave a comment below, with a photo if applicable, so that someone can help you!

By Aidan Weeks

A passionate Mechanical Engineer with endless enthusiasm for fluid power - building off the back of over 18 years of high quality contribution and discussion stimulated by Bill Wade here at About Air Compressors. With both practical and theoretical experience in pneumatics and hydraulics, I'm putting my knowledge to work - and working my grey-matter through my research, assistance and publishing work here at About Air Compressors. Feel free to reach out any time! P.S. A HUGE shout out to Doug who really offers such great value to all visitors to About Air Compressors - once again, feeling like I'm standing on the shoulders of GIANTS by getting to work alongside such a great community

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The Most Common Air Conditioning Failures (And How To Repair Them)

T he air conditioner is a masterpiece of technological ingenuity that tames inclement weather conditions. Until it doesn't. Air conditioning systems, regardless of the type, have their own set of unique and, often unexpected, problems. And since the majority of American households have at least one air conditioner unit installed, chances are you have experienced failures firsthand. This is especially frustrating if it happens at the peak of summer when you need the cooling breezes the most.

Air conditioning failures come in all forms and degrees of severity. Some, including dirty air filters, drainage problems, and a freezing condenser coil, can be easy to fix without having to look for a technician. But others, such as a damaged compressor and capacitor failure, would call for a professional to handle them. These usually imply that one or more parts of the unit are malfunctioning and should be replaced. Between those two extremes, other problems of mild severity might pop up. Then, you can either put on your technician hat and try to fix it yourself or take the costlier, yet easier, route of calling an expert. Read more to find out the most common air conditioning failures and how to fix them.

Read more: Reasons Why Your Toilet May Keep Clogging

The Thermostat Isn't Functioning Correctly

After setting the thermostat to the ideal temperature, you usually have to wait for the mandatory first few minutes before the gentle, cool air flows in. But when that doesn't happen and the air in the room continues to be warm, humid, and sluggish, then something is off. You check the AC unit only to find out that the air it blows out is slightly cool at best, or balmy at worst. The air conditioner is not playing tricks on you. You may just have a malfunctioning thermostat.

Thermostat malfunctioning is a more common air conditioning failure than many people think. It can have a simple reason behind it, such as the batteries are dead and need to be replaced. But other more sinister causes could lead to thermostat damage. These include broken wires, corrosion, loose screws, or simply dirt build-up. If the thermostat uses batteries, that's the first thing to check. Replace them and see if that fixes the problem. Otherwise, you might have to call a professional to sort out the issue or replace the thermostat altogether.

Water Is Leaking From The Unit

It's not normal for water to leak out of the air conditioner either indoors or outdoors. But as you might expect, such mishaps can happen for a wide variety of reasons. If the water leakage is indoors, then the condensate drain pipe, where the moisture inside the AC unit safely drains out in the pan, might be clogged. Fungal build-ups that thrive in humid conditions are often the culprit behind the clogging. Switch off the air conditioner then use the manual to locate the condensate drain pipe. Mix equal amounts of vinegar and water or bleach and water and pour the liquid inside the drain pipe to kill the fungi and unclog it. However, if the drain pipe isn't clogged, then the condensate pump might be malfunctioning, and you'd need to have it replaced.

If the water is leaking from the compressor outside, then the issue could be damaged condensate pans, poor installation of the unit, or the seal has gone bad. Unfortunately, none of these problems should be fixed by consulting the manual and watching a YouTube video. You should turn off the AC unit and give the technician a call.

The Air Conditioner Is Making Noises

Air conditioners and noise don't, or at least, shouldn't, mix. No matter what type of air conditioner you have, a quality, well-functioning one should purr like a kitten. When loud noises come out of the AC after you turn it on, you may have a serious issue on your hands. These noises, when they happen, come in different tunes and pitches. A faint bubbling noise tells you that there may be a refrigerant leak, or that the unit has a lot of moisture build-up. A persistent clicking sound means that the capacitor may be malfunctioning, or the fan has debris and grime build-up. Meanwhile, a loud grinding sound is an omen that either the motor or the compressor is about to fail.

These noises can be serious warning signs. And you shouldn't trust your ear to distinguish between a faint bubbling noise and persistent clicking, let alone diagnose the cause of the failure. As with other serious issues regarding the air conditioning system, a professional should handle this one. They can determine the source and type of the noise and the best fix for such an issue.

The Air Filter Is Clogged

The AC air filter has one job to do: screen the airflow for specks of dust, lint, pet hair, and dead bugs and keep them from cycling through the house. Over time, the filter mesh can become clogged with these pollutants. It's a slow and steady process, but its impact is decisive. The airflow increasingly diminishes, and the AC takes longer to cool down your home. This, in turn, has other undesirable effects, including but not limited to a spike in the electricity bill, frozen evaporator coils, and acceleration of the wear and tear of the air conditioning unit.

Air conditioner filters come in two types: replaceable or reusable. Replaceable options can only be used once and you should replace these air filters every one to two months depending on the quality of the air in your home and whether anyone has allergies. But if you have a reusable air filter, sometimes called a washable air filter, you should clean it every few months. Switch off the AC and open the front panel to remove the air filter. Wash it with a mixture of warm water and detergent, then rinse it thoroughly.

The Capacitor Is Failing

Sometimes the air conditioning system seems to be working. The condenser is humming, and the fan is whirring as it should, but the temperature indoors isn't decreasing. When the AC is running but fails to regulate the temperature, it's time to investigate the capacitor. These come in two varieties: start capacitors and run capacitors. A failing start capacitor doesn't provide the surge in power necessary to get the system running, while a bad run capacitor switches off the unit in the middle of a cooling cycle. The reasons for such failures vary but can be summed up as normal wear and tear, exposure to a heat source, and frequent power spikes.

AC capacitors are built to last and you can get around 20 years of service out of them, provided that they're not exposed to the sun or power surges. But when they fail, they could blow up and bring about damage to the other components. Call a technician and have them test the capacitor with a multimeter to determine if it's broken, in which case, it should be replaced.

The Air Conditioner Refrigerant Is Leaking

Leaking refrigerant, aka freon, is just as deceptive as a bad capacitor. In both cases, the compressor and the fan motor are working just fine, but the temperature indoors doesn't meet the thermostat setting. However, in the case of the leaking refrigerant, there's a serious health risk involved since the chemical is highly toxic. Some telltale signs that the AC refrigerant is leaking include frozen evaporator coils, dwindling cooling performance, and a hissing or gurgling sound coming out of the condenser.

Freon can leak from the AC unit due to shoddy installation or corrosion of the copper tubes, either because of friction or exposure to acidic chemicals. The system is also more likely to spring a leak if it's an old model where wear and tear has undermined the integrity of its components. Whatever the source, a leaking refrigerant is a serious system failure and you shouldn't try to fix it yourself. Stay away from the leaking AC to limit your exposure to the chemical and call a professional to handle it safely.

The Evaporator Coil Freezes Often

One name that keeps popping up whenever something goes wrong with the air conditioning system is the notorious evaporator coil and how it's prone to freezing. When ice covers those coils, the AC's cooling performance degrades, and the time it takes it to reach the set temperature becomes longer. The A-shaped evaporator coil with panels and coiled metal tubes is found near the system fan.

Unobstructed airflow is the key to a functional evaporator coil and a high-performing AC unit. If the system fan malfunctions, the airflow will slow down and the refrigerant inside the tubes will trigger ice to form on the coils. Or if dust and grime cover the coils, they could insulate the surface and freezing ensues. Yet another reason for poor ventilation could be a clogged air filter. To fix the issue, turn off the AC and use a hairdryer to melt the ice. Then clean or replace the air filters. You should also have the HVAC system serviced regularly to keep the fan in top shape and maintain the integrity of the coiled tubes.

The Circuit Breaker Trips When The AC Turns On

It's hard to miss this failure. When you switch on the AC or when the compressor kicks into gear to start a new cooling cycle, the circuit breaker will trip. As with other air conditioning problems discussed here, there's more than one source for this failure. It could simply be a bad or too-weak breaker that's at fault. Dirty condenser coils, clogged air filters, or a malfunctioning fan motor can all increase the power consumption of the unit and cause the fuse to blow. But the origin of the tripping could be more ominous and pricier when you have a failing compressor or a burnt-out motor.

Apart from the clogged air filters which you could clean or replace yourself, the rest of the issues should be handled by a professional. An electrician could replace or upgrade the circuit breaker just for the AC system, thus minimizing the recurring problem of overloading. As for the damaged motor, compressor, and fan motor, as well as the dirty condenser coils, a certified technician should look at them and suggest the best ways to repair or replace the malfunctioning parts.

The Air Conditioner Is Not Turning On/off

The air conditioner operational failures are not limited to poor performance and high energy consumption. Sometimes the AC won't turn on at all. Most likely, this is an electrical problem, so checking the circuit breaker and flipping the switch off and on may solve it. But it could also be a problem with a clogged air filter, so you should replace it or get it cleaned up. A malfunctioning condensate pump could also prevent the unit from working on account of moisture build-up. Consult the user manual to troubleshoot it for your specific model.

The other side of the problem is when the AC won't turn off. Most air conditioners have cooling cycles that last between 15 to 20 minutes at a time. If the system keeps running nonstop, check the thermostat and make sure it's working properly. The temperature might be set too low, so adjusting it a few degrees higher may prevent the system from running around the clock. If none of this works, take a closer look at the condenser and condenser coils for dirt build-up, and inspect the evaporator coils for signs of ice. Defrost them as needed and have a full inspection performed on the unit.

The Air Conditioner Stopped Working And The Thermostat Went Blank

The AC could switch off unexpectedly in the middle of a cooling cycle for any one of the reasons listed above. But the extra symptom, the thermostat going blank, adds an unwelcome twist to the plot. A common root of this failure is moisture backup in a clogged condensate line. When the moisture fills up the drain line, it gets diverted into a secondary pan. This pan has a float switch that cuts the power for the condenser, the thermostat, and the blower motor when the drained moisture reaches a certain level.

Algae and dirt pile up in the condensate line are the two guilty parties behind this snag. Before you call a contractor, locate the secondary drain pan which is usually fitted under the evaporator coil. If the pan is full of water, that will confirm the clogged condensate line diagnosis. Your technician will likely use compressed air to clear up the clogged line.

A Funky Smell Comes Out Of The Air Conditioner

Sometimes, the AC develops an affinity for emitting odors that range from off-putting to hazardous. A moldy scent is easy to track down to fungi and mildew growths in the drain pan, on the evaporator coils, or inside the ducts and vents. Wash the drain pan and the coils with soap and water and replace or clean the air filters. To clean any mold buildup in the ducts and vents, you'll need the help of a professional.

A persistent burning smell coming out of the vents is cause for alarm. It usually indicates that the components of the unit are overheating and could soon fail. Calling a technician is the right course of action here. On the other hand, a rotten smell wafting through the open vents is usually nothing more than a dead rodent that's found its way inside the ducts and will need to be removed. But the same cannot be said about a chemical- or nail polish-like smell oozing out. This is a sign of a Freon leak. Switch off the AC and call a technician immediately.

Read the original article on House Digest .

Commercial Driver Handbook

Section 6 of 15

Section 5: Air Brakes

This section tells you about air brakes. If you want to drive a truck, bus, or pull a trailer with air brakes, you need to read this section. If you want to pull a trailer with air brakes, you also need to read Section 6: Combination Vehicles in this handbook.

Air brakes use compressed air to make the brakes work. Air brakes are a good and safe way of stopping large and heavy vehicles, but the brakes must be well maintained and used properly.

Air brakes are really 3 different braking systems: service brake, parking brake, and emergency brake. The:

Service brake system applies and releases the brakes when you use the brake pedal during normal driving.
Parking brake system applies and releases the parking brakes when you use the parking brake control.
Emergency brake system uses parts of the service and parking brake systems to stop the vehicle in a brake system failure.

CDL Air Brake Requirements. For CDL purposes, a vehicle’s air brake system must meet the above definition and contain the following, which will be checked during the vehicle inspection test:

Air gauges.
Low pressure warning device(s).

If the vehicle you use for your road test does not have these components, your vehicle will not be considered as having an air brake system and you will have a “No Air Brakes” (“L”) restriction on your CDL.

A full service brake application must deliver to all brake chambers not less than 90 percent of the air reservoir pressure remaining with the brakes applied (CVC §26502).

The parts of these systems are discussed in greater detail in the following paragraphs.

5.1 – Parts of an Air Brake System

There are many parts to an air brake system. You should know about the parts discussed here.

5.1.1 – Air Compressor

The air compressor pumps air into the air storage tanks (reservoirs). The air compressor is connected to the engine through gears or a v-belt. The compressor may be air cooled or cooled by the engine cooling system. It may have its own oil supply or be lubricated by engine oil. If the compressor has its own oil supply, check the oil level before driving.

5.1.2 – Air Compressor Governor

The governor controls when the air compressor will pump air into the air storage tanks. When air tank pressure rises to the “cut-out” level (around 125 pounds per-square-inch or “psi”), the governor stops the compressor from pumping air. When the tank pressure falls to the “cut-in” pressure (around 100 psi), the governor allows the compressor to start pumping again.

5.1.3 – Air Storage Tanks

Air storage tanks are used to hold compressed air. The number and size of air tanks varies among vehicles. The tanks will hold enough air to allow the brakes to be used several times, even if the compressor stops working.

5.1.4 – Air Tank Drains

Compressed air usually has some water and some compressor oil in it, which is bad for the air brake system. The water can freeze in cold weather and cause brake failure. The water and oil tend to collect in the bottom of the air tank. Be sure that you drain the air tanks completely. Each air tank is equipped with a drain valve in the bottom. There are 2 types:

Manual —operated by turning a quarter turn or pulling a cable. You must drain the tanks yourself at the end of each day of driving. See Figure 5.1.
Automatic —the water and oil are automatically expelled. These tanks may be equipped for manual draining as well.

Automatic air tanks are available with electric heating devices. These help prevent freezing of the automatic drain in cold weather.

5.1.5 – Alcohol Evaporator

Some air brake systems have an alcohol evaporator to put alcohol into the air system. This helps to reduce the risk of ice in air brake valves and other parts during cold weather. Ice inside the system can make the brakes stop working.

Check the alcohol container and fill up as necessary. (every day during cold weather). Daily air tank drainage is still needed to get rid of water and oil (unless the system has automatic drain valves).

5.1.6 – Safety Valve

A safety relief valve is installed in the first tank the air compressor pumps air to. The safety valve protects the tank and the rest of the system from too much pressure. The valve is usually set to open at 150 psi. If the safety valve releases air, something is wrong. Have the fault fixed by a mechanic.

5.1.7 – The Brake Pedal

You engage the brakes by pushing down the brake pedal (It is also called a foot valve or treadle valve). Pushing the pedal down harder applies more air pressure. Letting up on the brake pedal reduces the air pressure and releases the brakes. Releasing the brakes lets some compressed air go out of the system, so the air pressure in the tanks is reduced. It must be made up by the air compressor. Pressing and releasing the pedal unnecessarily can let air out faster than the compressor can replace it. If the pressure gets too low, the brakes will not work.

5.1.8 – Foundation Brakes

Foundation brakes are used at each wheel. The most common type is the S-cam drum brake. The parts of the brake are discussed below.

Brake Drums, Shoes, and Linings. Brake drums are located on each end of the vehicle’s axles. The wheels are bolted to the drums. The braking mechanism is inside the drum. To stop, the brake shoes and linings are pushed against the inside of the drum. This causes friction, which slows the vehicle (and creates heat). The heat a drum can take without damage depends on how hard and how long the brakes are used. Too much heat can make the brakes stop working.

S-cam Brakes. When you push the brake pedal, air is let into each brake chamber. Air pressure pushes the rod out, moving the slack adjuster, thus twisting the brake camshaft. This turns the S-cam (it is shaped like the letter “S”). The S-cam forces the brake shoes away from one another and presses them against the inside of the brake drum. When you release the brake pedal, the S-cam rotates back and a spring pulls the brake shoes away from the drum, letting the wheels roll freely again. See Figure 5.2.

CamLaster. The CamLaster brake has 2 key design differences over traditional S-cam brakes.

One feature is a completely internal adjustment system which is designed to continually keep the brake in proper adjustment. S-cam brakes, on the other hand, require an external slack adjuster. The second feature is a unique cam design that applies the brake shoe. Unlike a standard drum brake that has either a single or double anchor-pin brake, the CamLaster slides the shoes down an inclined ramp on a cam to evenly contact the brake drum.

Wedge Brakes. In this type of brake, the brake chamber push rod pushes a wedge directly between the ends of 2 brake shoes. This shoves them apart and against the inside of the brake drum. Wedge brakes may have a single brake chamber or 2 brake chambers that push wedges in at both ends of the brake shoes. Wedge type brakes may be self-adjusting or may require manual adjustment.

Disc Brakes. In air-operated disc brakes, air pressure acts on a brake chamber and slack adjuster, like S-cam brakes. But instead of the S-cam, a “power screw” is used. The pressure of the brake chamber on the slack adjuster turns the power screw. The power screw clamps the disc or rotor between the brake lining pads of a caliper, similar to a large c-clamp.

Wedge brakes and disc brakes are less common than S-cam brakes.

5.1.9 – Supply Pressure Gauges

All vehicles with air brakes have a pressure gauge connected to the air tank. If the vehicle has a dual air brake system, there will be a gauge for each half of the system (or a single gauge with two needles). Dual systems will be discussed later. These gauges tell you how much pressure is in the air tanks.

5.1.10 – Application Pressure Gauge

This gauge shows how much air pressure you are applying to the brakes. (This gauge is not on all vehicles.) Increasing application pressure to hold the same speed means the brakes are fading. You should slow down and use a lower gear. Brakes that are of adjustment, air leaks, or mechanical problems can also cause the need for increased pressure.

5.1.11 – Low Air Pressure Warning

A low air pressure warning signal is required on vehicles with air brakes. A warning signal you can see must come on when the air pressure in the tanks falls between 55 and 75 psi (or 1/2 the compressor governor cutout pressure on older vehicles). The warning is usually a red light. A buzzer may also come on.

Another type of warning is the “wig wag.” This device drops a mechanical arm into your view when the pressure in the system drops between 55 and 75 psi. An automatic wig wag will rise out of your view when the pressure in the system goes above 55 and 75 psi. The manual reset type must be placed in the “out of view” position manually. It will not stay in place until the pressure in the system is above 55 psi.

On large buses, it is common for the low pressure warning devices to signal at 80–85 psi.

5.1.12 – Stop Light Switch

Drivers behind you must be warned when you put your brakes on. The air brake system does this with an electric switch that works by air pressure. The switch turns on the brake lights when you put on the air brakes.

5.1.13 – Front Brake Limiting Valve

Some vehicles made before 1975 have a front brake limiting valve and a control in the cab. The control is usually marked “normal” and “slippery.” When you put the control in the “slippery” position, the limiting valve cuts the “normal” air pressure to the front brakes by half. Limiting valves were used to reduce the chance of the front wheels skidding on slippery surfaces. However, they actually reduce the stopping power of the vehicle. Front wheel braking is good under all conditions. Tests have shown front wheel skids from braking are not likely even on ice. Make sure the control is in the “normal” position to have normal stopping power.

Many vehicles have automatic front wheel limiting valves. They reduce the air to the front brakes except when the brakes are put on very hard (60 psi or more application pressure). The driver cannot control these valves.

5.1.14 – Spring Brakes

All trucks, truck tractors, and buses must be equipped with emergency brakes and parking brakes. They must be held on by mechanical force (because air pressure can eventually leak away). Spring brakes are usually used to meet these needs. Powerful springs are held back by air pressure when driving. If the air pressure is removed, the springs put on the brakes. A parking brake control in the cab allows the driver to let the air out of the spring brakes. This lets the springs put the brakes on. A leak in the air brake system, which causes all the air to be lost, will also cause the springs to put on the brakes.

Tractor and straight truck spring brakes will come fully on when air pressure drops to a range of 20 to 45 psi (typically 20 to 30 psi). Do not wait for the brakes to come on automatically. When the low air pressure warning light, and buzzer first come on, bring the vehicle to a safe stop right away, while you can still control the brakes.

The braking power of spring brakes depends on the brakes being in adjustment. If the brakes are not adjusted properly, neither the regular brakes nor the emergency/parking brakes will work right.

5.1.15 – Parking Brake Controls

In newer vehicles with air brakes, you put on the parking brakes using a diamond-shaped, yellow, push-pull control knob. You pull the knob out to put the parking brakes (spring brakes) on, and push it in to release them. On older vehicles, the parking brakes may be controlled by a lever. Use the parking brakes whenever you park.

Caution. Never push the brake pedal down when the spring brakes are on. If you do, the brakes could be damaged by the combined forces of the springs and the air pressure. Many brake systems are designed so this will not happen. Not all systems are set up that way, and those that are may not always work. It is much better to develop the habit of not pushing the brake pedal down when the spring brakes are on.

Modulating Control Valves. In some vehicles a control handle on the dash board may be used to apply the spring brakes gradually. This is called a modulating valve. It is spring-loaded so you have a feel for the braking action. The more you move the control lever, the harder the spring brakes come on. They work this way so you can control the spring brakes if the service brakes fail. When parking a vehicle with a modulating control valve, move the lever as far as it will go and hold it in place with the locking device.

Dual Parking Control Valves. When main air pressure is lost, the spring brakes come on. Some vehicles, such as buses, have a separate air tank which can be used to release the spring brakes. This is so you can move the vehicle in an emergency. One of the valves is a push-pull type and is used to put on the spring brakes for parking. The other valve is spring loaded in the “out” position. When you push the control in, air from the separate air tank releases the spring brakes so you can move. When you release the button, the spring brakes come on again. There is only enough air in the separate tank to do this a few times. Therefore, plan carefully when moving. Otherwise, you may be stopped in a dangerous location when the separate air supply runs out. See Figure 5.3.

5.1.16 – Anti-lock Braking Systems

Truck tractors with air brakes built on or after March 1, 1997, and other air brakes vehicles (trucks, buses, trailers, and converter dollies) built on or after March 1, 1998, are required to be equipped with anti-lock brakes. Many commercial vehicles built before these dates have been voluntarily equipped with ABS. Check the certification label for the date of manufacture to determine if your vehicle is equipped with ABS. ABS is a computerized system that keeps your wheels from locking up during hard brake applications.

Vehicles with ABS have yellow malfunction lamps to tell you if something is not working.
Tractors, trucks, and buses will have yellow ABS malfunction lamps on the instrument panel.
Trailers will have yellow ABS malfunction lamps on the left side, either on the front or rear corner. Dollies manufactured on or after March 1, 1998, are required to have a lamp on the left side.

On newer vehicles, the malfunction lamp comes on at start-up for a bulb check, and then goes out quickly. On older systems, the lamp could stay on until you are driving over 5 mph.

If the lamp stays on after the bulb check, or goes on once you are under way, you may have lost ABS control at one or more wheels.
In the case of towed units manufactured before it was required by the DOT, it may be difficult to tell if the unit is equipped with ABS. Look under the vehicle for the ECU and wheel speed sensor wires coming from the back of the brakes.
ABS is an addition to your normal brakes. It does not decrease or increase your normal braking capability. ABS only activates when wheels are about to lock up.
ABS does not necessarily shorten your stopping distance, but it does help you keep the vehicle under control during hard braking.

SUBSECTION 5.1

Test Your Knowledge

Why must air tanks be drained?
What is a supply pressure gauge used for?
All vehicles with air brakes must have a low air pressure warning signal. True or False?
What are spring brakes?
Front wheel brakes are good under all conditions. True or False?
How do you know if your vehicle is equipped with anti-lock brakes?

These questions may be on your test. If you cannot answer them all, reread Subsection 5.1.

5.2 – Dual Air Brake

Most heavy-duty vehicles use dual air brake systems for safety. A dual air brake system has 2 separate air brake systems, which use a single set of brake controls. Each system has its own air tanks, hoses, lines, etc. One system typically operates the regular brakes on the rear axle or axles. The other system operates the regular brakes on the front axle (and possibly one rear axle). Both systems supply air to the trailer (if there is one). The first system is called the “primary” system. The other is called the “secondary” system. See Figure 5.4.

Before driving a vehicle with a dual air system, allow time for the air compressor to build up a minimum of 100 psi pressure in both the primary and secondary systems. Watch the primary and secondary air pressure gauges (or needles, if the system has 2 needles in one gauge). Pay attention to the low air pressure warning light and buzzer. The warning light and buzzer should shut off when air pressure in both systems rises to a value set by the manufacturer. This value must be greater than 55 psi.

The warning light and buzzer should come on before the air pressure drops below 55 psi in either system. If this happens while driving, you should stop right away and safely park the vehicle. If one air system is very low on pressure, either the front or the rear brakes will not be operating fully. This means it will take you longer to stop. Bring the vehicle to a safe stop, and have the air brakes system fixed.

One-Way Check Valve

This device allows air to flow in one direction only. All air tanks on air-brake vehicles must have a check valve located between the air compressor and the first reservoir (CVC §26507). The check valve keeps air from going out if the air compressor develops a leak.

5.3 – Inspecting Air Brake Systems

You should use the basic 7-step inspection procedure described in Section 2 to inspect your vehicle. There is more to inspect on a vehicle with air brakes than one without them. These components are discussed below, in the order that they fit into the 7-step method.

5.3.1 – During Step 2 Engine Compartment Checks

Check the air compressor drive belt (if the compressor is belt-driven). If the air compressor is belt-driven, check the condition and tightness of the belt. It should be in good condition.

5.3.2 – During Step 5 Walk Around Inspection

Check slack adjusters on S-cam brakes. Park on level ground and chock the wheels to prevent the vehicle from moving. Release the parking brakes so you can move the slack adjusters. Use gloves and pull hard on each slack adjuster that you can reach. If a slack adjuster moves more than about one inch where the push rod attaches to it, it probably needs adjustment. Adjust it or have it adjusted. Vehicles with too much brake slack can be very hard to stop. Out-of-adjustment brakes are the most common problem found in roadside inspections. Be safe. Check the slack adjusters.

All vehicles built since 1994 have automatic slack adjusters. Even though automatic slack adjusters adjust themselves during full brake applications, they must be checked.

Automatic adjusters should not have to be manually adjusted except when performing maintenance on the brakes and during installation of the slack adjusters. In a vehicle equipped with automatic adjusters, when the pushrod stroke exceeds the legal brake adjustment limit, it is an indication that a mechanical problem exists in the adjuster itself, a problem exists with the related foundation brake components, or the adjuster was improperly installed.

The manual adjustment of an automatic adjuster to bring a brake pushrod stroke within legal limits is generally masking a mechanical problem and is not fixing it. Further, routine adjustment of most automatic adjusters will likely result in premature wear of the adjuster itself. It is recommended that when brakes equipped with automatic adjusters are found to be out of adjustment, the driver takes the vehicle to a repair facility as soon as possible to have the problem corrected. The manual adjustment of automatic slack adjusters is dangerous because it may give the driver a false sense of security regarding the effectiveness of the braking system.

The manual adjustment of an automatic adjuster should only be used as a temporary measure to correct the adjustment in an emergency situation. It is likely the brake will soon be back out of adjustment since this procedure usually does not fix the underlying adjustment problem.

Automatic slack adjusters are made by different manufacturers and do not all operate the same. Therefore, the specific manufacturer’s service manual should be consulted prior to troubleshooting a brake adjustment problem.

Check Brake Drums (or Discs), Linings, and Hoses

Brake drums (or discs) must not have cracks longer than 1/2 the width of the friction area. Linings (friction material) must not be loose or soaked with oil or grease and must not be worn dangerously thin (less than 1/4 inch). Mechanical parts must be in place, not broken, or missing. Check the air hoses connected to the brake chambers to make sure they are not cut or worn due to rubbing.

5.3.3 – Step 7: Final Air Brake Check

All air brake system tests in this section are considered important and each can be considered critical parts of the in-cab air brakes tests. The items marked with an asterisk (*) in this section are required for testing purposes during the vehicle inspection portion of the CDL skills test. They may be performed in any order as long as they are performed correctly and effectively. If these items are not demonstrated and the parameters for each test are not verbalized correctly, it is considered an automatic failure of the vehicle inspection portion of the skills test.

Do the following checks instead of the hydraulic brake check shown in Section 2, Step 7: Check Brake System.

1. Applied Leakage Test (1-minute hold): *

To perform this test, the driver must start with the engine running and with the air pressure built to governor cut-out (120–140 psi or another level specified by the manufacturer). The driver identifies when cut-out occurred, shuts off the engine, chocks the wheels if necessary, releases the parking brake (all vehicles) and tractor protection valve (combination vehicle), and fully applies the foot brake. The driver then holds the foot brake for 1 minute after stabilization of the air gauge. The driver checks the air gauge to see that the air pressure drops no more than 3 pounds in one minute (single vehicle) or 4 pounds in 1 minute (combination vehicle) and listens for air leaks. The driver must identify how much air the system lost and verbalize the maximum air loss rate allowed for the representative vehicle being tested.

For a Class A combination vehicle, if the power unit is equipped with air brakes and the trailer is equipped with electric/surge brakes, the pressure drop should be no more than 3 psi.

3 psi for single vehicles.
4 psi for a combination of 2 vehicles.
6 psi for a combination of 3 or more vehicles.

The maximum air loss rate for a combination of 2 or more vehicles is 3 psi if the towed vehicles are not equipped with air brakes.

An air loss greater than those listed above, indicates a problem in the braking system and repairs are needed before operating the vehicle. If the air loss is too much, check for air leaks and fix any that are identified.

For testing purposes, you must be able to demonstrate this test and verbalize the allowable air loss for your vehicle. For testing purposes, identify if the air loss rate is too much.

2. Low Air Warning Device*

To perform this test the vehicle must have enough air pressure so the low-pressure warning signal is off. The engine maybe on or off; however, the key must be in the “on” or “battery charge” position. Next, the driver begins fanning off the air pressure by rapidly applying and releasing the foot brake. Low-air warning devices (buzzer, light, and flag) must activate before air pressure drops below 55 psi or the level specified by the manufacturer. The driver must indicate the approximate pressure when the device gave warning and identify the parameter at which this must occur; no lower than 55 psi. See Figure 5.5.

For testing purposes, identify and verbalize the pressure at which the low air pressure warning signal activates and identify the parameter(s) at which this should occur. On large buses, it is common for low-pressure warning devices to signal at 80–85 psi. If testing in a large bus, identify the parameter(s) mentioned above (55–75 psi) and inform the examiner that your vehicle’s low-pressure warning devices are designed to activate at a higher pressure.

If the warning signal does not work, you could lose air pressure and not know it. This could cause sudden emergency braking in a single-circuit air system. In dual systems, the stopping distance will be increased. Only limited braking can be done before the spring brakes come on.

Farm labor vehicles and Type I school buses must be equipped with both an audible and visible type warning device.

3. Spring Brake Test:*

To perform this test, the parking brake (all vehicles) and tractor protection valve (combination vehicles) must be released; (engine running or not) as the driver fans off the air pressure. Normally between 20-45 psi (or the level specified by the manufacturer) on a tractor-trailer combination vehicle, the tractor protection valve and parking brake valve should close (pop out). On other combination vehicle types and single vehicle types, the parking brake valve should close (pop out). The driver must identify and verbalize the approximate pressure at which the brake(s) activated.

The parking brake valve will not pop out on buses that are equipped with an emergency park brake air reservoir (tank). If your bus is equipped with an emergency park brake air tank, you must perform the spring brake test for triple reservoir vehicles to check the automatic actuation of the spring brakes.

Spring Brake Test for Triple Reservoir Vehicles

If the parking brake valve does not pop out when the air pressure has been reduced to approximately 20 psi, you must demonstrate that the spring brakes have activated. To do this, you must:

Remove the wheel chocks, if necessary.
Leave the parking brake valve in the open (released) position.
With the engine running, put the vehicle in a forward gear and attempt to drive forward.

The spring brakes should drag and prevent the vehicle from easily moving forward. If the spring brakes do not prevent the vehicle from easily moving forward, your road test will be postponed.

This test must only be performed on single vehicles designed with an isolated parking brake reservoir. Do not perform this test on combination vehicles.

Check the Rate of Air Pressure Buildup

To perform this test, the engine must be running at normal operating idle, typically 600–900 rpms. Observe the air gauge to determine if the pressure builds at the proper rate. For dual air systems, the pressure should build from approximately 85 to 100 psi within 45 seconds. For single air systems (in pre-1975 vehicles), the pressure should build from approximately 50 to 90 psi within 3 minutes.

For testing purposes, you must verbalize the parameters of the test and identify if the vehicle met the appropriate standards.

Test Air Leakage Rate

There are 3 tests as follows:

Static Leakage Test

With a basically fully-charged air system (within the effective operating range for the compressor), turn off the engine, release all brakes, and let the system settle (air gauge needle stops moving). Time for 1 minute. The air pressure should not drop more than:

2 psi for single vehicles.
3 psi for a combination of 2 vehicles.
5 psi for a combination of 3 or more vehicles.

The maximum air loss rate for a combination of 2 or more vehicles is 2 psi if the towed vehicles are not equipped with air brakes.

An air loss greater than those listed above, indicate a problem in the braking system and repairs are needed before operating the vehicle.

Test Parking Brake

Fasten your seat belt. Set the parking brake, and gently pull against it in a low gear to test that the parking brake will hold.

Test Service Brakes

Wait for normal air pressure, release the parking brake, move the vehicle forward slowly (about 5 mph), and apply the brakes firmly using the brake pedal. Note any vehicle “pulling” to one side, unusual feel, or delayed stopping action.

This test may show you problems, which you otherwise would not know about until you needed the brakes on the road.

SUBSECTIONS 5.2 AND 5.3

What is a dual air brake system?
What are the slack adjusters?
How can you check slack adjusters?
How can you test the low pressure warning signal?
How can you check the spring brakes come on automatically?
What are the maximum leakage rates?

These questions may be on your test. If you cannot answer them all, reread Subsections 5.2 and 5.3.

5.4 – Using Air Brakes

5.4.1 – normal stops.

Push the brake pedal down. Control the pressure so the vehicle comes to a smooth, safe stop. If you have a manual transmission, do not push the clutch in until the engine rpm is down close to idle. When stopped, select a starting gear.

5.4.2 – Braking With Anti-lock Brakes

When you brake hard on slippery surfaces in a vehicle without ABS, your wheels may lock up. When your steering wheels lock up, you lose steering control. When your other wheels lock up, you may skid, jackknife, or even spin the vehicle.
ABS helps you avoid wheel lock up. The computer senses impending lockup, reduces the braking pressure to a safe level, and helps you maintain control.
You may or may not be able to stop faster with ABS, but you should be able to steer around an obstacle while braking, and avoid skids caused by over braking.
Having ABS on only the tractor, only the trailer, or even on only 1 axle, still gives you more control over the vehicle during braking. Brake normally.
When only the tractor has ABS, you should be able to maintain steering control, and there is less chance of jackknifing. But keep your eye on the trailer and let up on the brakes (if you can safely do so) if it begins to swing out.
When only the trailer has ABS, the trailer is less likely to swing out. But if you lose steering control or start a tractor jackknife, let up on the brakes (if you can safely do so) until you gain control.
When you drive a tractor-trailer combination with ABS, you should brake as you always have. In other words: — Use only the braking force necessary to stop safely and stay in control. — Brake the same way, regardless of whether you have ABS on the tractor, the trailer, or both. — As you slow down, monitor your tractor and trailer and back off the brakes (if it is safe to do so) to stay in control. — There is only 1 exception to this procedure. If you always drive a straight truck or combination with working ABS on all axles, in an emergency stop, you can fully apply the brakes. — Without ABS, you still have normal brake functions. Drive and brake as you always have. — Remember, if your ABS malfunctions, you still have regular brakes. Drive normally, but get the system serviced soon.

5.4.3 – Emergency Stops

If somebody suddenly pulls out in front of you, your natural response is to hit the brakes. This is a good response if there is enough distance to stop, and you use the brakes correctly.

You should brake in a way that will keep your vehicle in a straight line and allow you to turn if it becomes necessary. You can use the “controlled braking” or “stab braking” method.

Controlled Braking. With this method, you apply the brakes as hard as you can without locking the wheels. Keep steering wheel movements very small while doing this. If you need to make a larger steering adjustment or if the wheels lock, release the brakes. Reapply the brakes as soon as you can.

Stab Braking. Apply your brakes all the way. Release the brakes when wheels lock up. As soon as the wheels start rolling, apply the brakes fully again. (It can take up to one second for the wheels to start rolling after you release the brakes. If you reapply the brakes before the wheels start rolling, the vehicle will not straighten out.)

5.4.4 – Stopping Distance

Stopping distance was described in Section 2.6 under “Speed and Stopping Distance.” With air brakes there is an added delay, “brake lag”. This is the time required for the brakes to work after the brake pedal is pushed. With hydraulic brakes (used on cars and light/medium trucks), the brakes work instantly. However, with air brakes, it takes a little time (one half second or more) for the air to flow through the lines to the brakes. Thus, the total stopping distance for vehicles with air brake systems is made up of 4 different factors.

Perception Distance + Reaction Distance + Brake Lag Distance + Braking Distance = Total Stopping Distance

The air brake lag distance at 55 mph on dry pavement adds about 32 feet. Therefore, at 55 mph for an average driver under good traction and brake conditions, the total stopping distance is over 450 feet. See Figure 5.6.

5.4.5 – Brake Fading or Failure

Brakes are designed so that brake shoes or pads rub against the brake drum or discs to slow the vehicle. Braking creates heat, but brakes are designed to take a lot of heat. However, brakes can fade or fail from excessive heat caused by using them too much and not relying on the engine braking effect.

Excessive use of the service brakes results in overheating and leads to brake fade. Brake fade results from excessive heat causing chemical changes in the brake lining, which reduce friction, and cause expansion of the brake drums. As the overheated drums expand, the brake shoes and linings have to move farther to contact the drums, and the force of this contact is reduced. Continued overuse may increase brake fade until the vehicle cannot be slowed down or stopped.

Brake fade is also affected by adjustment. To safely control a vehicle, every brake must do its share of the work. Brakes out of adjustment will stop doing their share before those that are in adjustment. The other brakes can then overheat and fade, and there will not be enough braking available to control the vehicle(s). Brakes can get out of adjustment quickly, especially when they are hot. Therefore, check brake adjustment often.

5.4.6 – Proper Braking Technique

Remember, the use of brakes on a long and/or steep downgrade is only a supplement to the braking effect of the engine. Once the vehicle is in the correct low gear, the following is the proper braking technique:

Apply the brakes just hard enough to feel a definite slowdown.
When your speed has been reduced to approximately 5 mph below your “safe” speed, release the brakes. (This application should last for about 3 seconds.)

When your speed has increased to your “safe” speed, repeat steps 1 and 2.

If your “safe” speed is 40 mph, you would not apply the brakes until your speed reaches 40 mph. You now apply the brakes hard enough to gradually reduce your speed to 35 mph and then release the brakes. Repeat this as often as necessary until you have reached the end of the downgrade.

5.4.7 – Low Air Pressure

If the low air pressure warning comes on, stop and safely park your vehicle as soon as possible. There might be an air leak in the system. Controlled braking is possible only while enough air remains in the air tanks. The spring brakes will come on when the air pressure drops into the range of 20 to 45 psi. A heavily loaded vehicle will take a long distance to stop because the spring brakes do not work on all axles. Lightly loaded vehicles or vehicles on slippery roads may skid out of control when the spring brakes come on. It is much safer to stop while there is enough air in the tanks to use the foot brakes.

5.4.8 – Parking Brakes

Any time you park, use the parking brakes, except as noted below. Pull the parking brake control knob out to apply the parking brakes and push it in to release. The control will be a yellow, diamond-shaped knob labeled “parking brakes” on newer vehicles. On older vehicles, it may be a round blue knob or some other shape (including a lever that swings from side to side or up and down).

Do not use the parking brakes if the brakes are very hot (from just having come down a steep grade), or if the brakes are very wet in freezing temperatures. If they are used while they are very hot, they can be damaged by the heat. If they are used in freezing temperatures when the brakes are very wet, they can freeze so the vehicle cannot move. Use wheel chocks on a level surface to hold the vehicle. Let hot brakes cool before using the parking brakes. If the brakes are wet, use the brakes lightly while driving in a low gear to heat and dry them.
If your vehicle does not have automatic air tank drains, drain your air tanks at the end of each working day to remove moisture and oil. Otherwise, the brakes could fail.

Never leave your vehicle unattended without applying the parking brakes or chocking the wheels. Your vehicle might roll away and cause injury and damage .

SUBSECTION 5.4

Why should you be in the proper gear before starting down a hill?
What factors can cause brakes to fade or fail?
The use of brakes on a long, steep downgrade is only a supplement to the braking effect of the engine. True or False?
If you are away from your vehicle only a short time, you do not need to use the parking brake. True or False?
How often should you drain air tanks?
How do you brake when you drive a tractor-trailer combination with ABS?
You still have normal brake functions if your ABS is not working. True or False?

These questions may be on your test. If you cannot answer them all, reread Subsection 5.4.

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10 Reasons Why Your Air Compressor Keeps Tripping the Breaker

Table of Contents

Air Compressor Trips The Breaker As Soon As It Starts

Air Compressor Trips Breaker After Running for a Few Seconds (Or Longer)

Can a bad compressor trip a breaker?

What is a common problem fault on an air compressor?

How do I stop my air compressor from tripping the breaker?

Can An Air Compressor Be Laid Down or Stored on Its Side?

Why Does My Air Compressor Keep Tripping The Breaker

Five-minute read

10. Low Refrigerant Level of an Air Conditioner Compressor:

10 Possible Factors & How To Solve Them:

1. Overloading of the Circuit:

2. Poor Insulation on the Air Compressor:

3. Dust or Dirt in the Motor:

4. Faulty Electrical Wiring:

5. Improperly Sized Circuit Breaker:

6. Excessive Voltage Drop:

7. Poor Engine Performance:

8. Faulty Pressure Switch:

9. Leak in Compressor Line:

Conclusion:

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Why Does My Air Compressor Keep Tripping the Breaker?

1. Shorted Air Compressor

Troubleshooting Air Compressor: Keeps Tripping Reset & Blowing Fuses

How to Troubleshoot an Air Compressor That Keeps Tripping on Reset & Blowing Fuses

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Air Compressor Keeps Tripping Reset? (We Have a Fix!)

Do You Need Appliance Repair Services?

A Reset Button’s Purpose

Air Compressors

Three Basic Types

Not Enough Power

What’s the Fix?

Running the Compressor Too Long

Sticking Centrifugal Switches

Tripping the Circuit Breaker

Unloader Valve

Pressure Switch

Are Your Air Compressor Vents and Filters Clear?

Is Your Air Compressor Properly Maintained?

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