Midea HB-A60/CGN8-B - Appendix To Part 4

M thermal Split
202004 107
4.26 Pb Troubleshooting
Digital display output 4.26.1
Description 4.26.2
Water side heat exchanger anti-freeze protection.
M-Thermal Split stops running.
Error code is displayed on hydronic box main PCB and ANTI.FREEZE icon is displayed on user interface.
Possible causes 4.26.3
Normal system protection.
Temperature sensor not connected properly or has malfunctioned.
Hydronic box main PCB damaged.
Procedure 4.26.4
Pb
1. Outdoor ambient temperature 3°C and water side heat
exchanger water outlet temperature/water inlet
temperature/backup electric heater outlet water
temperature 5
2. Water side heat exchanger water outlet temperature/water
inlet temperature/backup electric heater outlet water
temperature 2
Yes
Normal system protection. The
system will resume
automatically
1
No
Water side heat exchanger water outlet temperature sensor,
water inlet temperature sensor or backup electric heater outlet
water temperature sensor loose
2
Yes
Ensure the temperature sensor
is connected properly
No
Water side heat exchanger water outlet temperature sensor,
water inlet temperature sensor or backup electric heater outlet
water temperature sensor has short-circuited or failed
3
Yes
Replace the temperature sensor
No
Replace outdoor main PCB
Notes:
1. Refer to Part 3, 5.7 Water Side Heat Exchanger Anti-freeze Protection Control .
2. Final outlet water temperature sensor, water side heat exchanger water inlet temperature sensor and water side heat exchanger water outlet temperature
sensor connections are port CN6 on the hydronic box main PCB (labeled 10 in Figure 4-2.1 in Part4, 2.2 "Main PCB for Hydronic System").
3. Measure sensor resistance. If the resistance is too low, the sensor has short-circuited. If the resistance is not consistent with the sensor s resistance
characteristics table, the sensor has failed. Refer to Part 2, 1.2 and to Table 4-5.3 in Part 4, 5.1
.
5 Appendix to Part 4
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