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8
5 Open circuit or short circuit of temperature sensor diagnosis and solution (E4/E5/F1/F2/F3)
Error Code
E4/E5/F1/F2/F3
Malfunction decision
conditions
If the sampling voltage is lower than 0.06V or higher than 4.94V, the LED
will display the failure.
Supposed causes
●
Wiring mistake
●
Sensor faulty
Check the connection
between temperature
sensor and PCB.
Correct the connection
No
Yes
Replace indoor or outdoor
main PCB
Measure the resistance
value of the sensor
Repalce the sensor
No
Yes
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 ...