Midea V8 VRF Series Service Manual page 53

V8 VRF Indoor Units
6.1.11 b11, b13 - Error in 1# electronic expansion valve coil, error in 2# electronic expansion valve coil
Error display
The faulty IDU stops. Other IDUs of the same system: operate normally.
Error impact
ODU of the same system: operate normally.
The IDU main control board cannot detect the feedback signal from the electronic expansion valve
Error trigger
coil for no less than 4 seconds.
Error recovery
After the unit is powered on again, the main control program detects a feedback signal from the
electronic expansion valve.
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Possible cause
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Troubleshooting
52
Digital display
The electronic expansion valve coil plugged into the EXV port in the IDU main control board
is loose.
The IDU main control board is damaged.
The electronic expansion valve coil is faulty.
The electronic expansion valve coil is short circuited or disconnected.
b11/b13 (1)
Is the
electronic expansion
valve coil plugged into the
EXV port in the IDU main
control board
loose?
No
Check the
electronic expansion valve
Is the coil abnormal
(2)?
No
Check
the electronic
expansion valve
Is the coil adapter
short circuited or
disconnected
(3)?
No
Replace the main control
board of the IDU
Display position
Panel, display box, and wired controller
Yes
Reconnect the plug tightly
Yes
Replace the electronic
expansion valve coil
Yes
Replace the adapter