4230 <4330> (U5) Heat sink temperature trouble

What does 4230 <4330> (U5) mean?

This error indicates an issue with the heat sink temperature in the outdoor unit. It could be caused by blockages in the fan or airflow path, a faulty fan motor, high ambient temperatures, or a defective temperature sensor.

• Blocked outdoor fan.
• Malfunction of outdoor fan motor.
• Blocked airflow path around the outdoor unit.
• Rise of ambient temperature.
• Characteristic defect of thermistor.
• Malfunction of input circuit on outdoor power board.
• Malfunction of outdoor fan driving circuit.

Click steps to track your progress.

1. 1

   Turn off the power to the outdoor unit at the circuit breaker.

2. 2

   Inspect the outdoor unit for any blockages, such as leaves, dirt, or debris, that might be obstructing the fan or airflow path.

3. 3

   Ensure the outdoor fan is spinning freely by gently trying to rotate it by hand (once power is off and it's safe).

4. 4

   Check that there is adequate clear space around the outdoor unit for proper airflow.

5. 5

   If the problem persists, a service technician will need to check the fan motor, thermistor, and circuit board.