Is It Normal for the Car's Fan to Keep Running When the Air Conditioner Is On?
3 Answers
Yes, it is normal. When the air conditioner is turned on, the air conditioning compressor starts working and requires the fan to dissipate heat. Here is some related information: 1. Introduction: Car air conditioning refers to the air conditioning device installed in a car, which can cool, heat, ventilate, and purify the air inside the cabin, providing a comfortable environment for passengers, reducing driver fatigue, and improving driving safety. 2. Structure: It generally includes a cooling device, a heating device, and a ventilation device. This combined system makes full use of the limited space inside the car, has a simple structure, and is easy to operate, making it a popular modern car air conditioning system internationally.
My car has been running for ten years, and it's quite common for the AC fan to keep spinning, especially during hot summers or in traffic jams when the fan needs to operate continuously to maintain proper cooling. This is entirely to protect the compressor system and prevent overheating damage. However, I've also experienced abnormal situations, like when the fan kept running and making strange noises—it turned out to be a faulty temperature sensor falsely reporting high temperatures, causing the fan to stay on. Another possible issue is a stuck fan relay or an aging fan motor, where the fan runs unnecessarily, even after parking, increasing power consumption. I recommend checking if the coolant temperature gauge rises normally; if it doesn’t but the fan keeps running, visit a repair shop immediately for diagnostics. Regular maintenance, like cleaning the fan blades, is also crucial, as dust buildup can affect performance. In short, most of the time, the fan running is a good sign, indicating the AC is working effectively to dissipate heat.
From my understanding of automotive systems, the fan running continuously when the air conditioning is on is mostly by design. The fan is responsible for cooling the AC condenser to prevent excessive internal pressure. Under normal operating conditions, the fan cycles on and off intermittently to control temperature, but in high external temperatures, it may run continuously to avoid loss of cooling. If the fan always runs non-stop, especially in low-load environments like cool weather, be alert—it could be due to low refrigerant levels causing pressure imbalance or a short circuit in the fan control circuit. Once during a repair, I noticed loud fan bearing noise, and the diagnosis revealed severe wear in the fan motor requiring replacement. Regularly checking the pressure readings of the AC system can prevent failures. Abnormal fan operation can increase fuel consumption, so early troubleshooting is advisable. Don’t let small issues accumulate into major problems.
