Willis WST12MC16S Service Manual page 43

Indoor fan does not rotate without feedback
n detection point:
Mai
Is the control panel reliably connected with the electromotor? Is it loose? Is the connecting sequence correct?
Is the input voltage within the normal range (measure the voltage between L and N of the wiring block XT with AC voltage gauge.)
Malfunction diagnosis process:
Temperature sensor malfunction
Main detection point:
Is outdoor ambient temperature within the normal range?
Is indoor and outdoor fan running normally?
Is the radiating environment inside and outside the unit good enough?
Malfunction diagnosis process:
Energize the
unit and start it
Voltage between L
and N of indoor
wiring block
Check the
connec ting
Y
Voltage > 200V?
state of the
connecting terminal
N
Check power supply
Adjust
Reliable
N
connection
connecting state
Y
Replace main
remove the
N
board of
indoor unit
remove the N
error?
Replace motor
Finish
error?
Y
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