Denso Air Conditioner Error Code FL

The FL code on a Denso air conditioner means the overcurrent relay, also called a thermal relay, has tripped due to excessive current in the fan motor circuit. The relay opens its contact to cut power to the fan motor and protect the system from damage. This is a protective fault that requires diagnosis of the fan motor and related components before the unit can resume normal operation.

No, it is not safe to continue operating the unit while the FL code is active. The system has shut down specifically to prevent motor overheating and potential electrical damage. Running the unit repeatedly through reset cycles without addressing the cause can lead to more extensive and costly repairs.

Clearing or resetting the FL code does not fix the underlying problem. The thermal relay trips in response to a real overcurrent condition, so the code will return if the fan motor, capacitor, or supply voltage issue is not corrected. A proper repair requires identifying and resolving the cause of the excessive current draw before the system can operate reliably.

The thermal relay will reset on its own once it cools down, and the FL code may clear temporarily after a reset. However, if the underlying cause is not corrected, the relay will trip again and the fault will return. Repeatedly cycling the unit without fixing the root cause can accelerate motor failure and risk additional component damage.

Repair costs depend entirely on which component has failed. A replacement run capacitor is typically a low-cost repair in the range of $50 to $150 including labor. A failed fan motor replacement can range from $200 to $600 or more depending on the unit model and labor rates in your area. Diagnosing the specific fault first will prevent unnecessary parts replacement.