Signs It’s Time To Replace Your Car A/C Compressor

Signs It's Time To Replace Your Car A/C Compressor

Modern automotive A/C systems are more advanced and efficient than ever before but like anything made by man they are prone to failure. There are a number of signs that you need to replace the car’s A/C compressor, and the sooner you do it, the better.

What Is The Purpose of A Compressor?

The compressor is to air conditioning what your heart is to your body; it promotes the circulation for essential fluid, in this case, refrigerant rather than blood. As its name suggests, it is also responsible for compressing refrigerant, transforming it from the gas state into fluid, and then transferring it to a condenser which will perform a heat exchange where heat is extracted from the refrigerant. Next, the refrigerant will enter the expansion valve where it resumes a gaseous state. The accumulator is another key component as it will remove refrigerant moisture at which point it will be sent to an evaporator and finally into your vehicle.

The Compressor Clutch Has Gone Bad

Each compressor has a clutch that is attached to an engine via a pulley and belt. The clutch allows a compressor to cycle off and on instead of constantly being used. This lowers the amount of compressor wear while also providing superior fuel economy because engines don’t need to activate the compressor during times it isn’t required for providing cold air.

However, the clutch itself can fail. This usually occurs when it becomes stuck inside an on position that results in a compressor constantly turning while the vehicle is being driven. Or it might stop working completely, meaning its compressor will never be engaged. Both scenarios are bad, and while the clutch is reparable in some scenarios, more often the wiser solution is to simply replace it outright.

You’re Hearing Noises Beneath The Hood

Any type of sound being emitted from beneath your hood is bad. Your A/C compressor is responsible for circulating and compressing refrigerant. This requires it to cycle off and on many times during use and because it is a demanding task internal components may eventually fail. The sound you’re hearing is most likely the sealed bearing which has either seized up or worn out, particularly if its bearing lubricant is leaking. This could culminate in a grinding noise or a higher-pitched squeal. 

When a bearing seizes, the squealing comes from its drive belt which can no longer spin your compressor. While there are circumstances where the compressor may be repaired, many mechanics will recommend simply replacing it.

The Air Becomes Cool, Rather Than Cold

A classic sign that you’ve got a problem with your A/C compressor is air coming from the vents which gets cool, but not cold. In situations where you’ve activated the A/C, turned down the temperature, and have your fan cranked up, and the air still isn’t becoming as frigid as in the past, it probably isn’t your imagination. Rather, it is often an early symptom of an A/C that is becoming faulty and is the result of either a system leak or the compressor is wearing out.