There could be several reasons why the fan of a split air conditioner stops suddenly. Here are a few possible causes:
Power interruption: The most common reason for the fan to stop suddenly is a power interruption. Check if the air conditioner has lost power or if there is a tripped circuit breaker or blown fuse. In such cases, restoring power or resetting the breaker should resolve the issue.
Motor malfunction: The fan motor in the air conditioner may have encountered a malfunction. This could be due to a faulty motor, damaged wiring, or a problem with the motor's capacitor. A malfunctioning motor may cause the fan to stop running suddenly.
Overheating: If the air conditioner's motor or other components overheat due to prolonged usage or inadequate ventilation, the built-in safety mechanisms may shut down the fan to prevent damage. Ensure that the air conditioner has proper airflow and is not obstructed by debris or furniture.
Control board or sensor issues: The control board or sensors responsible for detecting the fan's operation may have encountered a fault. This could be due to a wiring issue, a malfunctioning control board, or a faulty sensor. In such cases, professional assistance may be required to diagnose and fix the problem.
Faulty fan relay: The fan relay is an electrical component that controls the operation of the fan. If the fan relay malfunctions or fails, it may cause the fan to stop working suddenly. A faulty relay may need to be replaced to restore proper fan operation.
Other electrical or component failures: There may be other electrical or component failures within the air conditioner system that could cause the fan to stop suddenly. Examples include problems with the thermostat, capacitor, or wiring connections. Identifying and rectifying these issues often require professional expertise.
It's important to note that troubleshooting and repairing an air conditioner should be done by qualified technicians. If your air conditioner's fan is repeatedly stopping suddenly or you are unsure about the cause, it is recommended to contact an HVAC professional to diagnose and resolve the problem safely.