M thermal Mono
202004 75
4.16 P1 Troubleshooting
Digital display output
Description
Discharge pipe high pressure protection. When the discharge pressure rises above 4.2MPa, the system displays P1
protection and M thermal Mono stops running. When the discharge pressure falls below 3.2MPa, P1 is removed and
normal operation resumes.
Error code is displayed on refrigerant system main control board for refrigerant system and user interface.
Possible causes
Pressure sensor/switch not connected properly or has malfunctioned.
Excess refrigerant.
System contains air or nitrogen.
High pressure side blockage.
Poor condenser heat exchange.
Main PCB damaged.