There can be several reasons why the fan of a split air conditioner stops suddenly. Some of the common causes include:
Thermostat Setting: The fan may stop running if the thermostat reaches the set temperature and signals the air conditioner to shut off. Once the room temperature matches the desired setting, the air conditioner cycles off to save energy.
Fan Mode Selection: If the air conditioner is set to the "Auto" mode, the fan will automatically stop when the desired temperature is reached. However, if it's set to the "On" mode, the fan will run continuously regardless of the temperature, and it won't shut off until you manually turn it off.
Faulty Fan Motor: A faulty fan motor could cause the fan to stop suddenly. This could be due to issues such as electrical problems, worn-out bearings, or a burned-out motor.
Safety Features: Modern air conditioners are equipped with safety features that can shut down the fan or the entire unit if they detect a potential problem, such as overheating or a malfunctioning component.
Blocked Airflow: If the evaporator coil or the condenser unit becomes blocked with dirt, debris, or ice, it can cause the fan to stop running. This blockage restricts the airflow, leading to issues with the cooling process and potential damage to the system.
Faulty Capacitor: The fan motor uses a capacitor to start and run smoothly. If the capacitor becomes faulty or fails, the fan may stop functioning.
Electrical Issues: Problems with the electrical supply or wiring could lead to the fan not receiving the necessary power to operate.
Defective Fan Relay: The fan relay is responsible for controlling when the fan turns on and off. If the relay is faulty, it may cause the fan to stop abruptly.
Thermal Overload: Air conditioner fans can have thermal overload protection to prevent the motor from overheating. If the motor gets too hot, the thermal overload switch can trigger, shutting off the fan until the motor cools down.
If you experience your split air conditioner's fan stopping suddenly and it's not due to reaching the desired temperature or the fan mode selection, it's essential to have a professional HVAC technician inspect the unit. Attempting to troubleshoot or repair electrical or mechanical components yourself can be dangerous and may void the warranty. A qualified technician can diagnose the issue accurately and perform the necessary repairs to get your air conditioner running smoothly again.