Midea R32 M thermal Arctic Mono fault P0

What it means

Indicates suction pipe low pressure protection. When the suction pressure falls below 0.14MPa, the system displays P0 protection and M thermal Mono stops running. When the pressure rises above 0.30MPa, P0 is removed and normal operation resumes.

Likely causes

1. Low pressure switch not connected properly or has malfunctioned. Insufficient refrigerant. Low pressure side blockage. Poor evaporator heat exchange in heating mode or DHW mode. Insufficient water flow in cooling mode. Main PCB damaged.
2. Suction pressure drops below 0.14MPa
3. Low refrigerant charge
4. Blocked evaporator/water side heat exchanger
5. Low pressure switch signal off for extended period
6. Refrigerant undercharge, evaporator blockage, expansion device malfunction, suction line restriction
7. Insufficient refrigerant caused by refrigerant leakage
8. Low pressure side blockage
9. Poor evaporator heat exchange in heating mode or DHW mode
10. Low pressure side blocked by crushed or bent pipe, blocked EXV, or dirty filter

Where to start

1. Monitor suction pressure continuously
2. Check for refrigerant leakage and insufficient refrigerant. Inspect low pressure side for blockages caused by crushed or bent pipe, blocked EXV, or dirty filter. Check air side heat exchanger, fan(s) and air outlets for dirt/blockages in heating or DHW mode. Check water side heat exchanger, water piping, circulator pumps and water flow switch for dirt/blockages in cooling mode.
3. Measure suction pressure Pe