5 Signs and Symptoms of a Bad Home AC Compressor

What Is an Air Conditioner Compressor?

So, what function does your AC compressor serve?

AC compressors are responsible for heat-transfer functions that bring the cooled and conditioned air into the various rooms of your house. It’s the component that pumps refrigerant throughout the unit, allowing it to produce cool air. Air conditioners need refrigerant to cool down the warm air your AC system absorbs from your home. However, refrigerant is a gas and it needs help from machinery to cool down the air.

The process works the following way: Refrigerant needs to go through a cycle that turns it from gas to liquid to gas again. The cycle begins when the compressor turns the low-pressure refrigerant into a high-pressure, high-temperature gas. The gas then goes through the condenser, which then turns the refrigerant into a cool liquid. Then it enters the evaporator coils, which turn it into a cool gas. The process is repeated continuously, with all parts working together as a team to keep your home cool.

If you have a faulty compressor, the rest of the parts will be missing a crucial component, leaving you with no cold air.

Fluid Leakage

Compressor Leakage // Source
Compressor Leakage // Source

Another potential symptom that can signal a malfunctioning compressor is the leakage of fluids from it. As noted above, there are bearings within the compressor that generally prevent any kind of fluid or refrigerant leakage. However, a worn-out/broken bearing can cause fluid to leak leading to the compressor’s ultimate failure.


Fluid Leaks

Your vehicle’s air-conditioning compressor has internal bearings, as mentioned above, that prevent the refrigerant from leaking out of the compressor. The compressor’s job is to pressurize the refrigerant to help cool it down. This, of course, wears the bearings down over time because of the constant pressurized environment inside the compressor. Worn or damaged bearings will leak refrigerant.

AC Compressor Not Turning On: Common Reasons

There are many possible reasons your window AC compressor may not be turning on. Reasons your AC compressor may not be turning on include the following.

1. Power

If your fan is running but your AC compressor is not, the outer unit housing the compressor may be the culprit. The unit may not be receiving power, and the fan may continue to run.

If the AC compressor isn’t starting, inspect the wiring connecting the two units. Potential causes could be a tripped circuit breaker, a blown fuse, mismatched indoor and outdoor units, a faulty thermostat or an old AC unit.

2. Dead Compressor

A dead compressor may result from an overheating unit or a faulty capacitor. If you have a dead compressor, your only option would be to replace the unit. In this case, you should always call a professional to install the replacement.

3. Capacitor and Starter Relay Problems

Your system’s capacitors and starter relays are integral in supplying power to the compressor. While the capacitor provides the power needed to run the outer fan, blower motor and compressor, the starter relay transmits power to the compressor from the capacitor.

If capacitor and start relay problems cause your AC compressor not to turn on, chances are your compressor is trying to access a capacitor that is not operating properly.

4. Dirty Coil and Filters

Your AC compressor may shut down entirely due to a buildup of dirt and debris in the condenser soil, evaporators or filters. The evaporator coil may stop functioning altogether due to a blockage. Condenser coils and clogged air filters put the compressor under pressure, causing it to overheat.

If you find your AC compressor is continuously overheating, you may have to replace the unit. To allow air to flow freely, clear out obstructions and blockages, replace the air filters and wash the condenser coils.

4. Circuit Breaker Tripping

Circuit breakers are good things. A circuit breaker trips because it’s protecting your home from a potential fire. Normally it happens when too many appliances run at the same time, which overloads the system. If the outside condensing unit consistently loses power and trips a circuit breaker, it may mean that the compressor is about to fail. It’s a sign that the compressor is overheating and needs too much power to do its job.

When you go to the circuit breaker panel to switch the system back on, remember that if the breaker is hot, it’s not a good sign. You need emergency HVAC services immediately.

5. Leaks Around the Air Conditioning Unit

Moisture or puddles spotted anywhere near your HVAC system could be an indicator of a refrigerant leak. As noted above, this issue is a potentially hazardous one that could cause health problems. Some of the problems associated with a refrigerant leak include irritated eyes, nausea, headaches and coughing. If you spot a leak, you should call an HVAC professional immediately.

A leak beside your unit might also be a sign that it has a blocked or a broken drain tube, meaning the tube can no longer rid the unit of condensation. Such a problem isn’t a serious one, but don’t leave it to worsen. If you do, it could lead to more serious issues like rust or mold.

6. Warm Air Instead of Cool Air Being Delivered to the House

Air conditioning compressors can fail in any one of a number of ways. Some ways allow them to continue to operate and pump air into your home. This air, however, will not be cool. If you’re getting only warm air out of the air vents in your home, it’s a sign that your compressor is failing or that it’s low on refrigerant.

7. Reduced Airflow

Reduced airflow is another sign that your A/C compressor is failing. In fact, it’s one of the best early warning signs. This one may be a little harder to notice, but put your hands near a vent to feel the flow of air. If it seems weak and not as cool as it should be, you’ll know you have a compressor problem. If you hear your air conditioner working, put your hands to the vent. If you don’t feel air flowing into the room, it’s likely an indicator of a problem with your compressor.

8. Higher Electricity Bills

This sign of a problem is the one many homeowners notice first. An A/C system costs a lot to operate — it’s probably one of your home’s most expensive items. If you’re using your air conditioning system as you normally would but seem to be paying more for that normal use, the problem could be the compressor. If this component is having to work harder to cool the air in your home, the unit itself will run more often and need more electricity to run, which means you’ll receive higher bills.

Diagnosing Possible Problems

It shouldn’t take too long to find any problems with your AC compressor clutch. All you need is a few simple tools to complete the inspection.

Inspect the Clutch

Get a flashlight and check out the compressor clutch – really get in there! The majority of the times a clutch fails, there will be a burnt or discolored area. The clutch disc operates near flexible rubber isolators. Thanks to those, the disc can move smoothly. When the heat becomes unbearable, the isolators start to melt, giving a rusty color.

If you see these signs in your compressor clutch, you have to replace the whole compressor.

Jump Compressor

In case there aren’t obvious signs of a broken compressor clutch, you have to perform further diagnosis. First, unplug the connectors of the compressor and attach jumper connectors to the electromagnet.

You’ll need a wire crimp tool for this as the connectors are tiny. Link the car battery to the wires. One of them should be connected to the negative battery terminal whereas the other route is attached to the positive side.

The compressor clutch will continue kicking if the electromagnet is okay. Take out the positive wires to free the clutch. This process can be repeated several times as needed to ensure the clutch is operational.

Every time the clutch is activated, you should hear a sound letting you know it’s engaged. If this doesn’t go according to plan, there might be a defective magnet on the compressor. You have to get that replaced.

AC Compressor Location

Your A/C compressor will usually be located somewh

Your A/C compressor will usually be located somewhere on the auxiliary drive belt. It will have 2 refrigerant pipes connected to the body of it and an electrical plug to provide power.

The AC compressors are usually located towards the bottom of the engine, below your alternator and power steering pump, so you may check from underneath your vehicle to see the compressor.

Can You Drive Your Car Around With a Bad AC Compressor Clutch?

If you suspect that you might have a bad AC compressor clutch in your car, you might wonder whether or not you have to fix it right away. Is it something that is going to require your immediate attention—or something you can get away with not fixing for a few months? It really all depends on a variety of factors.

First and foremost, you should consider if you’re going to be able to keep the interior of your car comfortable without relying on your AC system. If you live in a place that doesn’t get too hot, you may be able to keep on driving your car with a bad AC compressor clutch in it. You can simply roll your windows down to cool your car off rather than leaning on your AC system to do it.

But you should also consider the condition of your car’s AC system if you make the decision to keep on driving a car with a bad AC compressor clutch in it. A bad AC compressor clutch could cause the belt that drives your AC compressor to wear down way quicker than it should. That could result in damage being done to your AC compressor and leave you with a more costly repair job on your hands.

Outside of wreaking havoc on your AC compressor, a bad AC compressor clutch might also lead to problems with the serpentine belt in your car. You could be forced to replace that sooner than you may have expected to, too. It’s why you should strongly consider having AC compressor clutch replacement done right away.

How does an AC compressor work?

To know how to tell if AC compressor is bad we have to understand how the AC compressor works. To know how an AC compressor works, we must understand how the AC system operates.


Welcome to rxmechanic.com. We are an automotive mechanic blog that helps mechanics and car users to find the most recent and accurate technical and repair information for their cars. We recently created this blog site to enable us to share our knowledge with other automotive mechanics and car owners.

2. No cooling at all

In more severe cases, where the switch has completely failed, your AC system will completely cease to blow cold air. Without the cycling switch to activate the compressor’s clutch, the AC system will not be pressurized correctly, and the system will be unable to produce any cold air as a result.

If you begin to notice that the AC system is no longer functioning as it used to, and you suspect that the clutch cycling switch may have a problem, consider having the switch tested and replaced if necessary. It is also important to be aware that when replacing the clutch cycling switch, the AC system will need to be refilled with the proper amount of oil and refrigerant for the AC system. However, this is something that any professional technician, such as one from YourMechanic, should be able to take care of for you both quickly and precisely.

Related News


Leave a Reply

Your email address will not be published.