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12.3.1.3 indoor unit fan speed has been out of control
Power off, then restart the
unit
2 minutes
later. Is it still
displaying the error code?
Power off, then restart the
unit
2 minutes
later. Is it still
displaying the error code?
Shut off the power supply,
rotate the fan by hand. Does
it rotate properly?
Shut off the power supply,
rotate the fan by hand. Does
it rotate properly?
The unit operates normally.
The unit operates normally.
Find out the cause and
have it solved. For
example,
whether the fan
is blocked or the screws
which fix the fan are
tighten.
Find out the cause and
have it solved. For
example,
whether the fan
is blocked or the screws
which fix the fan are
tighten.
Check the wiring of fan
motor. Are all the
connections good?
Check the wiring of fan
motor. Are all the
connections good?
No
Yes
No
Correct the connections.
Correct the connections.
No
Replace the fan motor
Replace the fan motor
Yes
Yes
Replace the main PCB
Replace the main PCB
No
Check whether the main PCB
is normal through index 1?
Check whether the main PCB
is normal through index 1?
Yes
No
Index 1:
1: Indoor AC fan motor
Power on and set the unit running in fan mode at high fan speed. After running for 15 seconds, measure the
voltage of pin1 and pin2. If the value of the voltage is less than 100V(208~240V power supply)or 50V(115V
power supply), the PCB must have problems and need to be replaced.
2. Indoor DC fan motor(control chip is inside fan motor)
Power on and when the unit is in standby, measure the voltage of pin1-pin3, pin4-pin3 in fan motor
connector. If the value of the voltage is not in the range showing in below table, the PCB must have
problems and need to be replaced.
Summary of Contents for 38QUS018DS2 Series
Page 16: ...16 78 3 4 A5 Duct ...
Page 19: ...19 78 ...
Page 20: ...20 78 5 Wiring Diagram Outdoor 38QUS018DS2 Outdoor 38QUS027DS3 ...
Page 21: ...21 78 Outdoor 38QUS036DS4 High wall 42QHF009DS 42QHF012DS 42QHF018DS ...
Page 22: ...22 78 A5 Duct 42QSM009DS A5 Duct 42QSM012DS 42QSM018DS ...
Page 23: ...23 78 Four way cassette 42QTD009DS Four way cassette 42QTD012DS 42QTD018DS ...
Page 24: ...24 78 Console ...