Why does the car air conditioner keep cooling non-stop?

[SanGavin]

This is mainly because the vehicle's own temperature is relatively high and exceeds the set temperature, so the car air conditioner will continuously cool to lower the temperature inside the car. This is a normal phenomenon. Here is some additional information: Air conditioner operation: This situation where the car air conditioner keeps working non-stop is somewhat similar to the air conditioners used in daily life. When the air conditioner is turned on and set to a temperature of 26 degrees, it will start operating to lower the indoor temperature to 26 degrees before entering a dormant state. If the set temperature is never reached, the air conditioner will keep working continuously. Car owners don't need to worry too much, as long as the air conditioner compressor doesn't malfunction, it won't have a significant impact on the overall cooling system. Air conditioner compressors are mainly divided into: Fixed displacement compressors and variable displacement compressors. These two types work on different principles, but it's certain that the fluorine content has some effect on the air conditioner compressor. After all, the car air conditioner compressor is the heart of the car air conditioning and cooling system, so car owners should pay more attention to the daily maintenance of the air conditioner compressor.

[SanVanessa]

I've also experienced the issue of my car's A/C continuously cooling. There are actually several common causes: a faulty thermostat is the most typical, where it fails to detect the temperature drop inside the car, so the A/C won't shut off; sometimes the temperature sensor is mispositioned due to sun exposure, falsely reading the cabin as still hot; if the compressor control valve gets stuck, refrigerant keeps circulating; wiring shorts or control panel malfunctions can also cause this. I remember once on a long drive, the non-stop cooling caused fuel consumption to spike and even froze the vents—later diagnosed as a bad pressure switch. Never ignore such problems; get them checked at a professional repair shop early, as improper fixes could damage the entire A/C system.

[DiWilliam]

The issue of continuous air conditioning cooling should be examined from both internal and external perspectives. External factors such as a stuck cooling fan or an overheated radiator can trigger the protective continuous cooling mode of the AC. Inside the car, accidentally activating the MAX cooling mode, which is designed to run non-stop, could also be the cause. My neighbor once encountered a problem where the evaporator froze and got blocked—cold air couldn't come out, but the compressor kept running mindlessly. Another often-overlooked point is the use of low-quality refrigerant, which can cause abnormal pressure and force the compressor to run non-stop. If you smell a burning odor from the AC or hear unusual noises from the compressor, it's advisable to turn off the AC immediately and drive straight to a repair shop to check the electrical system and refrigerant pressure.

[DiValerie]

It's likely a malfunction in the temperature control system. Think of the AC system as an automatic temperature-regulating butler: the temperature sensor is its eyes, the control panel is the brain, and the thermostat is the switch. When the eyes fail (sensor malfunction) or the brain gets confused (control panel program error), the butler forgets to turn off the cooling. A stuck compressor clutch is also quite common—it's like the switch getting jammed in the ON position. Once, my old car had this issue—I popped the hood and the compressor was scorching hot to the touch. It was fixed after spending 300 to replace the clutch assembly. If you encounter this, turn off the AC button first; prolonged operation can fry the compressor.