What Causes the Abnormal Noise After Turning Off the Car Air Conditioner?
1 Answers
The abnormal noise after turning off the car air conditioner is mainly caused by the following three reasons: 1. Fan operation: After the air conditioner is turned off, the fan does not stop working immediately but continues to run for a while to dry the water on the evaporator to prevent mold. This is a normal phenomenon, and the fan will automatically stop after a few minutes. 2. Power transformer operation: The sound comes from the power transformer of the indoor unit control circuit. The power frequency transformer emits a 50 Hz hum when powered on, and the sound will disappear after the power is completely cut off. 3. Thermal expansion and contraction of the air conditioner shell: The air conditioner shell expands and contracts due to temperature changes, causing deformation and producing intermittent cracking sounds. The sound will stop when the internal temperature of the air conditioner is completely the same as the room temperature, which is a normal phenomenon.