Two Reasons Your Car's Air Conditioner Won't Cool Your Air

There's nothing quite as annoying as a car with an air conditioner that doesn't work, especially when summertime rolls around. Fortunately, it may not be as hard as you assume to get a malfunctioning AC system working again. If you would like to learn more about fixing a bad air conditioner, read on. This article will provide a troubleshooting guide for two of the most common problems.

Faulty Compressor

A properly functioning compressor is absolutely necessary in order for the air conditioner to run. The first step in dealing with this problem is to verify whether the compressor is engaging the way it should when you switch your AC on. This verification process is fairly simple: you simply have to check to see whether the belt that drives the compressor is moving.

Open your hood, start the car, turn the air conditioner on, and then get back out and take a look at the compressor. Is the belt actively engaging the compressor? If the answer is no, you will now want to check whether you can activate the compressor by directly connecting it to your car's battery. This is accomplished through the use of a fused jump wire.

If you are able to jump your compressor in this fashion, and if the result is the AC system that blows cold air, you now know two things. First, you know that your air-conditioning system contains an appropriate amount of refrigerant. Second, you know that your problem must be tied to one of two issues:

  • a faulty compressor clutch relay
  • a malfunctioning internal switch

If you could not get the compressor functioning with your jumper cable, the issue is probably a blown-out or malfunctioning compressor clutch. If the compressor jumped correctly, but the air conditioner only blew warm air, you'll want to determine whether there is enough refrigerant in the system.

Refrigerant Issues

Without an adequate supply of refrigerant, your air conditioner will be virtually useless. Yet even if you have enough refrigerant, your AC will not work if that refrigerant is not adequately pressurized. This can be tested through the use of a special pressure gauge, also known as a manifold gauge set.

The pressure gauge should be attached to the port on the high-pressure end of your air-conditioning system. This port can most often be found attached to the hose that connects the compressor to the condenser. Ensure that your pressure is no less than 45 psi. If your pressure seems okay, the problem is likely that you don't have enough refrigerant. You will need to recharge your system in order to get the refrigerant back up to the appropriate level. 

If you would like help with these steps, contact an auto AC-repair service near you.