Four Signs Your Car’s AC Compressor Is Going Bad

Four Signs Your Car’s AC Compressor Is Going Bad

Symptoms of Bad AC Compressor

  • CABIN TEMPERATURES HIGHER THAN NORMALThe first sign of a bad AC compressor is that the AC is not blowing air as cold as it once did. A bad or damaged compressor will not be able to properly regulate the refrigerant flow and as a result, the AC will not function properly. If you notice a decrease in airflow or you only get hot air blowing out from the vents when you turn on the AC, it is a clear indicator that your AC compressor is going bad and need to be replaced.
  • LOUD OR RATTLING NOISELoud noises when the AC is switched on is another symptom of a failing AC compressor. The AC compressor has several interior components and if they break, rattling noise can occur from an AC unit. A bad AC compressor will struggle to turn on and off and the ideal solution to this problem is replacing the AC compressor instead of trying to repair it.
  • MOISTURE LEAKSMoisture around your AC unit is an indication of a refrigerant leak. An AC compressor has its own internal bearings that prevent fluid from leaking and if they get worn out or damaged, the fluid could easily leak from them also the refrigerant leaks from the compressor increase the potentially harmful health concerns.
  • COMPRESSOR CLUTCH IS NOT MOVINGClutch not moving is the other sign of a problematic compressor. The clutch allows the AC compressor to use the engine power only when it is needed. If the clutch seizes, it will keep the compressor activated permanently and if the clutch breaks, the compressor will not be able to receive engine power.

AC compressor is the heart of the AC system and is important for keeping you and other passengers cool in the summer heat. Given above are the signs that can point to a bad AC compressor and the sooner you inspect these signs, the better are the chances of getting it repaired rather than replaced.

If you find the above information valuable then you may also like this blog Signs of a Bad Car Battery

What Does An AC Compressor Do?

The compressor in your car’s air conditioning system is the system’s heart. It’s essentially a miniature compressor powered by your auxiliary drive belt. Your auxiliary drive belt pulls power from your crankshaft when your engine rolls over and sends it to the pulley on your AC compressor.

Your AC compressor has a clutch installed in the pulley since not everyone uses their A/C all of the time they’re driving. As you turn on and off your air conditioner, this clutch engages and disengages the compressor. If your air conditioner is turned off, the compressor’s pulley will spin without turning the compressor’s internals.

The AC compressor is meant to boost the pressure and temperature of the refrigerant within the system when cooling. The heat that the refrigerant has gathered up from your evaporator can be released once it reaches your vehicle’s condenser because the gas-based refrigerant molecules are closely packed.


Air Conditioning System Operating Principle

Basically, the AC system works by 2 principles: evaporating liquids absorb heat, while condensation from vapor to liquid transmits heat to objects and their surroundings. 

The refrigerant is pumped from the compressor under high pressure and under high evaporation temperature. During this stage the refrigerant is pumped to the condenser or the hot rig in steam. At the condenser the temperature of the medium is very high, the fan blows the condenser, the vapor liquid is cooled, condensed into a liquid under high pressure and low temperature. 

The liquid refrigerant continues to circulate to the filter or desiccator, where the refrigerant is purified by absorbing all moisture and impurities. The expansion valve regulates the flow of liquid into the evaporator (evaporator). It lowers the pressure of the refrigerant. Due to the drop of pressure, the liquid becomes a vapor in the evaporator. 

AC system works by 2 principles, evaporating liqui
AC system works by 2 principles, evaporating liquids absorb heat, while condensation from vapor to liquid transmits heat to objects and their surroundings. Source: Drive2

During evaporation, the refrigerant absorbs heat in the car cabin. It means cooling the air mass in the cabin. The air taken from outside comes through the evaporator. Here, the air from the evaporator takes away a lot of energy through the radiator leaves, therefore the temperature of the air will be reduced very quickly. Meanwhile the moisture in the air will also condense and expose. At refrigeration platforms, when the liquid medium is at a high temperature, the pressure becomes a vapor liquid with a low temperature and pressure.

When this process takes place the refrigerant needs a lot of energy, so it takes energy from the air around the evaporator. The energy does not go away but converts from one form to another. The air loses energy, therefore the temperature drops, creating cold air. Refrigerant is in the vapor form, under high temperature and low pressure, returned to the compressor.

AC Compressor Working Principle

The compressor is housed within the condenser unit and the component that starts the chain reaction cools the refrigerant. It should be noted that heat moves toward cooler areas. When the room temperature air passes through the evaporator unit, heat is eliminated from the air. The heat from the air passes along to the refrigerant, which is then fed into the compressor.

AC compressor operating principle.
AC compressor operating principle.

The refrigerant is then compressed, which condenses into a fluid, and is then released under pressure. At this point, the refrigerant is much hotter than when it came in, but the heat is then dissipated through the condenser coils. By the time it reaches the end of the loop, the refrigerant is cold again and fed into the evaporator coils. This cycle continues as long as the air conditioner is turned on and the output becomes hot air instead of cold. 

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.

Final Verdict:

The air conditioning compressor is one of the critical components of a vehicle’s air conditioning system. It is in charge of pressurizing the AC system and maintaining the refrigerant flowing to function properly. Because the air conditioner functions in a constant cycle of on and off, it is prone to wear every time it is turned on. It will ultimately fail and need to be replaced, just like every other component on a car.

Because the compressor is in charge of pressurizing and distributing the refrigerant, any problems with it will impact the remainder of the AC system. Car maintenance is critical, and many people overlook the need for car air conditioning. When you see bad AC compressor symptoms, it’s recommended to assess and fix it.

List of Signs That Indicate Your Car A.C. Compressor Needs Replacements

If you suspect some problem with your car air compressor, you can do a few things to get rid of the ailment.

1)The first and the most obvious sign to note is that the ac might not be cooling as efficiently as before. A damaged compressor will not be able to regulate the refrigerant flow properly resulting in improper functioning of the ac.

2)A failing ac compressor also sometimes makes a loud noise when switched on. Since ac compressors are difficult to repair, replacing of the entire unit seems a much easier option.

3)Another problematic sign may be that the clutch is not moving. The clutch can seize or break, meaning that the compressor is not able to receive enough engine power.

4)In case you are not getting sufficient air from the vents, you can check the vents for any kind of obstructions. The cabin air filter can be completely clogged which leads to imperfect airflow.

5)It is also advisable to always check the car fuse box before deciding to replace the car air compressor. A bad ac compressor can be the main source of any kind of refrigerant leaks. So, it is equally important to check those leaks.

Signs of a Failed Car AC Compressor

Your AC will give out warning signs to help you figure the problem. Since your ac compressor functions to pressurize and distribute the refrigerant, any problem with its function will affect the overall cooling, also resulting in hot air blowing from your AC.

Like every other car component, the compressor is also subject to consecutive wear and tear with the air conditioner’s continuous switching on and off. Once it is affected, the car ac compressor will eventually start sending signals that will notify the driver of a repair that is most certainly needed.

AC Compressor Replacement Cost

So after the diagnosing of the AC compressor, we are now reviewing the cost for replacing the AC compressor. The AC compressor is a very significant component of any vehicle. It will not be cheap to replace the compressor after it goes bad.

Usually, it takes $800 to $1.200 for the whole replacement of the compressor. It includes the component itself will cost anywhere from $650 to $1.000 or more. The labor costs will be anywhere from $150 to $200.

DIY AC Compressor Troubleshooting

First, try to turn your home’s thermostat to the lowest temperature possible. This should make the outside unit kick on, which will allow you to judge whether the air conditioning is turning on at all. If the outside AC unit kicks on but sounds different from usual, this could signal a problem. You may be hearing the fan running, rather than both the fan and the AC compressor.

If neither are running, turn the circuit breaker off for about a minute. Turn it back on and make sure the outdoor service switch is on and running. If this doesn’t fix the problem, check both the AC compressor condensing coil and fan to make sure there are no obstructions or blockages preventing it proper operation.

Unnaturally High Cabin Temperatures

Unnaturally High Cabin Temperature // Source
Unnaturally High Cabin Temperature // Source

Having a failed AC is something nobody likes. No matter what time of the season it is, one of the initial symptoms of a failing compressor is when your car AC is not blowing cool air at all. This leads to unnaturally high temperature inside the cabin.

While an AC not blowing cool air can mean many things, a failed compressor is surely one of them. Hence checking for your ac compressor can very well lead to you solving the cooling issues as well.

Unusual Car AC Sounds

When your car’s air conditioning system makes unusual noises, this often indicates an AC compressor problem. Unlike refrigerant leaks, this is a sign of a mechanical shift somewhere in your car’s air conditioner. One of the most active parts within your vehicle AC system is the compressor—making it a likely culprit. 

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.

Get a Free Estimate

When it comes to your AC, preparation is key – and we want to help you be prepared without the headache. To get a free quote on your unit’s installation, reach out to us today.

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.

Vehicle AC Repair Services

When your car’s air conditioner stops working, you can bring it to the local mechanics at Chapel Hill Tire. Our vehicle air conditioning services will restore your AC functioning and leave you driving happy. We proudly serve drivers throughout the greater Triangle area with our 9 locations across Durham, Raleigh, Carrboro, Apex, and Chapel Hill. We invite you to make your appointment here online or give your nearest Chapel Hill Tire a call to get started today!

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