Carrier 38MGR Series - DIAGNOSIS AND SOLUTION: FAN ISSUES; Indoor Fan Speed Out of Control (E0;E4)

34 Specifications subject to change without notice. 38MGR-04SM
DIAGNOSIS AND SOLUTION
Indoor fan speed has been out of control (E0/E4)
Troubleshooting
ERROR CODE E0/F4
MALFUNCTION DECISION
CONDITIONS
When the indoor fan speed remains low (300RPM) for certain period of time, the unit stops and the LED
displays the failure.
SUPPOSED CAUSES
• Wiring mistake
• Fan assembly faulty
• Fan motor faulty
• PCB faulty
Shut off the power supply
and turn it on 1 minute
later. Is it still displaying
the error code?
Shut off the power supply,
rotate the fan by hand.
Does it rotate properly?
The unit operates normally.
Determine the cause
and solve it.
For example, check
whether the fan is
blocked or the bearing
is broken.
Check the fan motor wires.
Are all the connections good?
No
Yes
No
Correct the connections.No
Yes
Check whether the
main PCB is normal.
Yes
Yes
Check whether the fan
motor is normal
(review Index 1).
Yes
Replace the fan motor.
Replace the
main PCB.
The
malfunction
is resolved.
No
No
If the
malfunction
still exists,
replace the
main PCB.
No