Midea R32 M thermal Arctic Mono fault EC

What it means

Balance tank sensor Tbt2 error (serial number 13). Displayed on user interface and refrigerant system main PCB.

Likely causes

1. Sensor Tbt2 disconnected, sensor malfunction, wiring break, PCB connection issue
2. Sensor Tbt2 fault
3. Sensor wiring fault
4. Main board fuse damaged/blown
5. Hydronic box main PCB fault
6. Damaged cables between hydronic box main PCB and outdoor unit main PCB
7. Outdoor unit main PCB fault
8. Incorrect or abnormal input power supply (N or L)
9. Sensor not connected properly
10. Sensor short-circuited
11. Sensor resistance inconsistent with characteristics table
12. Pressure sensor failure
13. High pressure side blockage
14. Air side heat exchanger, fan or air outlet dirt/blockage
15. Water side heat exchanger, water piping, circulator pump or water flow switch dirt/blockage
16. Insufficient refrigerant caused by refrigerant leakage
17. Low pressure side blocked by crushed or bent pipe, blocked EXV, or dirty filter
18. Poor air side heat exchanger heat exchange in heating or DHW mode
19. Insufficient water flow rate in cooling mode
20. Outdoor main PCB fault (last resort)

Where to start

1. Identify sensor type based on fault code
2. Locate corresponding port on refrigerant system main PCB for that model
3. Check connection at identified port