1503 (P6) Freeze protection of Branch box or Indoor unit

What does 1503 (P6) mean?

This error indicates that the freeze protection mechanism for the branch box or indoor unit has been activated. This can be caused by incorrect piping, miswiring of units or LEVs, or a malfunction of the LEV.

• Wrong piping connection between indoor unit and branch box.
• Miswiring between indoor unit and branch box.
• Miswiring of LEV (Linear Expansion Valve) in branch box or indoor unit.
• Malfunction of LEV in branch box or indoor unit.

Click steps to track your progress.

1. 1

   Turn off the power to the entire system at the circuit breaker.

2. 2

   Inspect all piping connections between the indoor unit and the branch box to ensure they are correct.

3. 3

   Check all wiring connections between the indoor unit and branch box for proper hook-up and secure connections.

4. 4

   Verify the wiring of the LEV (Linear Expansion Valve) in both the branch box and indoor unit.

5. 5

   Restore power to the unit. If the error persists, contact a qualified technician to inspect the LEV for malfunction.