Samsung Air Conditioner Error Code OPER_TIMER_FLICKER

OPER_TIMER_FLICKER indicates that the indoor unit heat exchanger temperature sensor has been detected as open or shorted. The control board reads the sensor at connector CN43 and triggers this code when the signal falls outside the valid range. The sensor is responsible for monitoring the indoor coil temperature to protect the system and regulate operation.

It is not recommended to continue operating the unit with this error active. The heat exchanger temperature sensor is a protective component, and without accurate coil temperature readings, the system cannot properly prevent coil freezing or overheating. Continued operation in this state could lead to additional component damage.

Repair costs vary depending on the root cause. Replacing the indoor heat exchanger temperature sensor is typically the least expensive repair, with parts generally ranging from $15 to $60 and labor costs depending on your region and service provider. If the indoor control board requires replacement, total costs including parts and labor can range from $150 to $400 or more. Getting a diagnostic visit from a certified technician is the best way to determine the exact cause before committing to parts.

Begin by checking the resistance of the indoor heat exchanger temperature sensor at connector CN43 on the indoor unit control board. If the resistance is out of range, the sensor itself should be replaced. If resistance reads correctly at the sensor but the fault remains, inspect the wiring harness for damage and check the connection at CN43 for corrosion or looseness. A persistent fault after ruling out sensor and wiring issues may point to a failed control board.

A power reset may temporarily clear the error display, but the code will return if the underlying sensor fault is still present. Because the fault is tied to a hardware condition, either an open or shorted sensor circuit, it cannot be permanently resolved without diagnosing and repairing the sensor, wiring, or control board.