What are the troubleshooting methods for intermittent cooling and heating in car air conditioning?
2 Answers
Car air conditioning may experience intermittent cooling and heating due to the following issues: damaged compressor capacitor; dirty filter; insufficient refrigerant. Below are the detailed explanations:1. Damaged compressor capacitor: For the air conditioning to function properly, both the internal and external units must work in coordination. If the car air conditioning exhibits intermittent cooling and heating, check if the external unit's compressor start capacitor is damaged. If it is, replacement is necessary.2. Dirty filter: If the air conditioning has not been cleaned for a long time, it can also cause intermittent cooling and heating. A dirty filter or evaporator can lead to poor ventilation and heat dissipation, causing the compressor to overheat and shut down. Therefore, regular cleaning is essential to maintain cleanliness.3. Insufficient refrigerant: Proper cooling requires an adequate amount of refrigerant. If the car's interior temperature fluctuates between hot and cold, check if the refrigerant in the air conditioning system is insufficient. If so, use other methods accordingly.
I've been driving for twenty years and have encountered the issue of air conditioning blowing hot and cold several times. The most common cause is insufficient or leaking refrigerant, especially in older cars where rubber hoses deteriorate and are prone to seepage. Adding some Freon usually solves the problem. Last time, I found the condenser clogged with willow catkins—after rinsing it clean with a water hose, the cooling immediately returned to normal. If the compressor's electromagnetic clutch has poor contact, you'll hear a clicking noise while driving, which requires lifting the car to check the coil voltage. A faulty thermostat can also cause erratic temperature fluctuations, so I keep an OBD scanner handy to monitor the data stream. Minor issues can be handled DIY, but for problems involving pipelines or electrical circuits, it's best to visit a repair shop for peace of mind—after all, losing AC suddenly in summer is too dangerous.
