Why does the car air conditioner sometimes blow cold and sometimes hot?

[ManuelLynn]

The reasons why the car air conditioner sometimes blows cold and sometimes hot are: 1. Dirty air filter; 2. Damaged blower or air conditioning flap motor; 3. Insufficient refrigerant in the air conditioning system; 4. Dirty radiator or condenser; 5. Faulty air conditioning pressure sensor or evaporator box sensor. The car air conditioning system includes cooling devices, heating devices, and ventilation devices. This combined system makes full use of the limited space inside the vehicle with a simple structure. The car air conditioner is used to adjust and control the temperature, humidity, air cleanliness, and air flow inside the car compartment to an optimal state, providing passengers with a comfortable riding environment, reducing travel fatigue, creating good working conditions for the driver, and serving as an important ventilation device for ensuring safe driving.

[SadieAnn]

My old car's AC often acts up like this too - it suddenly stops blowing cold air while driving, then cools down again after a while. Inspection revealed it might be due to a slipping compressor clutch. When it gets stuck or worn out, the refrigeration cuts off, causing temperature fluctuations inside the car. Insufficient refrigerant or leaks could also be a factor, with unstable pressure leading to poor cooling performance. A clogged expansion valve may trigger similar issues. If the cooling fan fails, the condenser overheats, activating the protection mechanism that makes the AC alternate between cold and hot. Driving in summer carries higher risks as heat waves can distract drivers. It's best to get professional inspection promptly, refill refrigerant or replace components when needed. Regular maintenance can prevent these problems - remember to ventilate the car properly when parked for safety.

[OKathryn]

Having experienced several instances of abnormal air conditioning, I believe the most common cause is a minor malfunction in the refrigeration system. If the compressor isn't working properly or there's a refrigerant leak, causing fluctuating pressure, the air conditioning will alternate between cooling and warming. Additionally, if the expansion valve is clogged with impurities, it can also lead to interrupted cooling. I've tried simple troubleshooting myself, but ultimately, it requires a technician to test with a pressure gauge. I recommend paying close attention to the performance of the air conditioning in daily use and not delaying when issues arise. After repairs, the comfort level increases significantly, and it also avoids high fuel consumption.

[VanMaximus]

The unstable air conditioning performance is truly disheartening, as it leads to resource wastage. This is often caused by refrigerant leaks or compressor malfunctions, resulting in low system efficiency that increases fuel consumption and emissions. Issues with the expansion valve may also exacerbate this phenomenon. It's advisable to use eco-friendly refrigerants and conduct regular checks on system sealing to minimize environmental impact.