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5
2 Indoor unit and outdoor unit communication protection error diagnosis and solution (E1)
Error Code
E1
Malfunction decision
conditions
Indoor unit does not receive the feedback from outdoor unit during 110
seconds and this condition happens four times continuously.
Supposed causes
●
Wiring mistake
●
Indoor or outdoor PCB faulty
Measure Vs, is it positive fluctuation?
(Vs is the voltage between S and N of
outdoor unit. Red pan-S, Black pan-N)
Measure Vs, is it positive fluctuation?
(Vs is the voltage between S and N of
outdoor unit. Red pan-S, Black pan-N)
Yes
Power off, then restart the unit 2 minutes later
Power off, then restart the unit 2 minutes later
No
Replace the outdoor main PCB.
Power on. Is the error
extinguished?
Replace the outdoor main PCB.
Power on. Is the error
extinguished?
Check the outdoor wiring connection
Check the outdoor wiring connection
Replace the indoor main PCB.
Power on. Is the error
extinguished?
Replace the indoor main PCB.
Power on. Is the error
extinguished?
Yes
Replace the outdoor main PCB.
Replace the outdoor main PCB.
No
Replace the indoor main PCB.
Replace the indoor main PCB.
No
Check the indoor wiring connection
Check the indoor wiring connection
Yes
Yes
Check whether reactor
is normal?
Check whether reactor
is normal?
Yes
Replace the reactor
Replace the reactor
No
Summary of Contents for 38QUS012DS
Page 1: ...SERVICE MANUAL 12 18 24K LIGHT COMMERCIAL ...
Page 5: ...2 PRODUCT LINEUP ...
Page 6: ...3 UNIT MODEL INDENTIFICATION ...
Page 7: ...PART 1 GENERAL INFORMATION 1 1 DUCT ...
Page 9: ...2 INSTALLTION SPACE ...
Page 10: ...3 STATIC PRESSURE ...
Page 11: ...4 STATIC PRESSURE 42QSM012DS ...
Page 12: ...5 STATIC PRESSURE 42QSM018DS ...
Page 13: ...6 STATIC PRESSURE 42QSM024DS ...
Page 18: ...11 5 Screw off the fixing screws to remove the evaporator 1 screw ...
Page 19: ...PART 1 GENERAL INFORMATION 1 2 CASEETTE ...
Page 22: ...3 INSTALLTION SPACE ...
Page 29: ...PART 1 GENERAL INFORMATION 1 3 UNDER CEILING ...
Page 31: ...3 INSTALLTION SPACE ...
Page 37: ...PART 1 GENERAL INFORMATION 1 4 OUTDOOR UNIT ...
Page 44: ...8 compressor on bottom plate 4 Lift the compressor from the base pan assembly ...
Page 45: ...PART 2 ELECTRICAL DIAGRAM ...
Page 46: ...1 WIRING DIAGRAM 42QSM012 18 24DS ...
Page 47: ...2 WIRING DIAGRAM 42QTD012 18DS ...
Page 48: ...3 WIRING DIAGRAM 42QTD024DS ...
Page 49: ...4 WIRING DIAGRAM 42QZL018 24DS ...
Page 50: ...5 WIRING DIAGRAM 38QUS012DS ...
Page 51: ...6 WIRING DIAGRAM 38QUS018DS ...
Page 52: ...7 WIRING DIAGRAM 38QUS024DS ...
Page 53: ...PART 3 TROUBLE SHOOTING ...