Midea Heat pump fault E8

What it means

Water flow protection triggered by no-water detection failures before pump on, or water flow switch breaks after pump on within 10 occurrences.

Likely causes

1. No water flow before pump on
2. Water flow switch failure/break after pump on
3. Incorrect dip switch configuration for pump type
4. Water flow restriction or blockage
5. Air in water system
6. Flow switch FS plug (CN8) is not connected properly
7. The water flow in the pipe is not consistent with arrow on the flow switch
8. Water flow switch rake mechanically damaged
9. Water flow switch mechanically damaged (rake does not trigger contact closure)
10. Flow switch leak due to faulty sealing ring
11. External pump starts before internal pump (PUMPI) starts
12. Flow switch not installed properly
13. Pump stalling due to impeller obstruction
14. Water pump internal failure despite correct wiring
15. Water pump malfunction indicated by abnormal indicator light status
16. Water pump leak due to faulty sealing ring
17. Water pump connection is correct, the water pump icon on the User Interface is lit, while no indicator lights on water pump is lit
18. Pump idling
19. Pump idling due to insufficient water/air in circuit

Where to start

1. Locate water flow switch, water pump, air purge valve, water inlet and water outlet using this layout when diagnosing E0/E8 faults
2. Verify DIP switch S2 positions 3/4 match installed pump type
3. Locate CN28 PUMP connector to check power supply to water pump