Why Does the Car Air Conditioning Suddenly Become Hot?
3 Answers
The reasons why a car's air conditioning suddenly becomes hot are as follows: 1. Compressor capacitor failure: For the air conditioning to operate, both the internal and external units need to work together. If the car air conditioning suddenly becomes hot, check if the external unit's compressor start capacitor is damaged. If so, it needs to be replaced. 2. Dirty filter: If the air conditioning has not been cleaned for a long time, it can also cause the air conditioning to suddenly become hot. A dirty filter or evaporator can easily lead to poor ventilation and heat dissipation, causing the compressor to overheat and shut down. Therefore, regular cleaning is necessary to maintain cleanliness. 3. Moisture in the air conditioning system: When the temperature of the pressure-reducing capillary tube and evaporator drops below 0 degrees, any remaining moisture in the tubes begins to freeze, causing blockages. Since the refrigerant cannot flow smoothly through the pipes, the cooling efficiency gradually decreases, and the temperature starts to rise. At this point, the air coming out of the vents will be hot (natural air).
Last time I drove to the countryside, the air conditioning suddenly stopped cooling and turned hot, which really annoyed me. I learned a few tricks from a car repair guy: the most common issue is running out of refrigerant—if it's leaking, the AC can't cool. It could also be a broken compressor, which is responsible for pressurizing the refrigerant; if it fails, the cycle won't work. Clogged fans or radiators can also cause hot air to blow out. Sometimes, the thermostat malfunctions, leading to inaccurate temperature sensing. It's best to get it checked quickly to prevent further damage. Driving without AC in summer is unbearable and affects safety, so I recommend visiting a professional shop to test refrigerant levels and compressor condition to avoid small issues turning into big expenses. Regular maintenance of the AC system is crucial—cleaning filters and checking wiring can prevent such surprises.
My old car's AC has been acting up lately, suddenly blowing hot air, which is really annoying. There are several possible reasons: refrigerant leaks are the most common, as the pipes can loosen over time with mileage. Compressor failure is also frequent - when it stops working, you lose all cooling. It could also be a control system malfunction, maybe a broken button or computer program error. Another possibility is the fan not spinning, causing poor heat dissipation that turns cold air into hot air. Don't delay - pull over and check it immediately by feeling the vent temperature or listening to the compressor sound. If you're not experienced, don't mess with it yourself; it's safer to have a professional look at it to avoid wasting money. This situation shows the importance of regular car maintenance - you should at least have the AC system checked annually.
