11
8 Operation current protection (F0)
Current protection of compressor
Judge 1: Check whether the
input current of the power
supply wire is higher than max
protection current value
Yes
Replace the electric control box
Check whether
the refrigerant
system is ok
Judge 2: Check whether the
outdoor ambient
temperature is higher than
50
℃
No
Stop the unit
Yes
Judge 3: Check whether the
outdoor unit is bad ventilation
No
Make the outdoor unit ventilate well
Yes
Judge 5: The refrigerant
pipe is blocked
No
Let the refrigerant out, then use the high
pressure nitrogen or refrigerant to blow pipe,
vacuumize and charge the refrigerant again
Yes
Judge 4: Check whether the
heat exchanger is dirty
No
Clean the heat exchanger
Yes
Yes
Replace outdoor main
board,and check whether
the system can run normally
No
Yes
Trouble is solved
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 ...