Car Air Conditioning Stops Cooling After a While
2 Answers
Car Air Conditioning Stops Cooling After a While The reasons and solutions for a car air conditioner that stops cooling after a while are as follows: 1. Too much refrigerant. When the car is driving at high speed, the engine speed is fast, and the pressure in the cooling system is high. The pressure controller (pressure switch) activates, causing the compressor to stop, and the air conditioning cooling ceases. When the car slows down, the engine speed decreases, the pressure in the cooling system drops, the pressure switch closes, the compressor resumes operation, and cooling is restored. Hence, the cooling is intermittent. 2. Lack of Freon. The usual cause of this issue is a leak in the air conditioning system's pipes. To detect the leak, you can drip some water at the refrigerant pipe joints of the car; bubbles will appear at the leaking spot. Once the leak is found and repaired, you can visit a professional car repair shop or a 4S store to add Freon.
I repaired a car with the same issue last week. Usually, the A/C is quite cool when first started, but after driving for twenty minutes, it starts blowing hot air. This situation is most likely due to refrigerant leakage or insufficient refrigerant; if the pressure in the A/C system is too low, it will stop working. A malfunctioning cooling fan or a condenser clogged with leaves can also cause the A/C to overheat and shut down as a protective measure. Another common issue is a faulty evaporator temperature sensor—if it falsely reports high temperatures, the compressor will shut off prematurely. When I was adding refrigerant to Old Zhang's car last time, I noticed oil stains at the low-pressure pipe connection, and sure enough, testing confirmed a leak. Remember, never add refrigerant yourself haphazardly—take it to a shop to have it checked with a pressure gauge; otherwise, you might waste money and damage the compressor or piping.
