Winterizing Your Car for Safe Driving

What To Do When Your Car's Air-Conditioning Stops Working

by Troy Fowler

The air-conditioning in your car may not be working correctly, and correcting the problem may involve an auto AC repair tech to correct the problem. If the air coming out of the vents is not cold, several things can be the cause, but most repair shops can test the system to determine what is causing the problem.

Low Refrigerant

One of the most common reasons that the air-conditioning in most cars stops working is because the refrigerant level in the AC system is too low. The system is pressurized with a specific amount of refrigerant, and if the level falls, the compressor and evaporator will no longer work correctly. 

The solution is to refill the system with refrigerant, but it needs to be done correctly, and it is essential to determine where the leak is so the tech can repair it. Recharging the system without fixing a leak will allow the new refrigerant to escape and the system to stop working again. 

When you take your car in for auto AC repair, the tech working on your vehicle will pressurize the system with air and look for leaks that need to be repaired. Often the tech will add some dye to the system to create a mark or indicator where the leak is, making it easier for the tech to fix the leak before recharging the system.

Broken Drive Belts

Many cars have an AC belt that is separate from the drive belt on the engine. If the belt breaks, it could come loose and fall onto the road under the car, allowing the AC compressor to stop, resulting in a loss of air-conditioning in the car. 

Inspecting the belts on your car should be a regular part of maintenance. Including the AC belt in that service is an excellent way to catch the problem before the belt completely fails. If there are cuts in the belt or missing chunks or if it is heavily glazed, the tech at the auto AC repair shop can replace and adjust the drive belt for you and inspect the AC system.

Damaged Evaporator

There is a heat exchanger used in your car's AC system mounted in front of the radiator for your engine. The evaporator passes refrigerant through it, and the air is drawn through the core to keep the material temperature regulated, so the system does not freeze up and works properly.

Because the evaporator sits in front of the radiator, damage can occur from rocks or road debris that could cause a small hole in the core. If the evaporator is leaking, it will cause the system pressure to drop, and the air will begin to get warm inside the car. Replacing the evaporator core and charging the system is not difficult, but your auto AC repair tech will need to verify the leak before doing any work.