Carrier 40MAHB Series Service Manual page 20

40MAHB: Service Manual
DIAGNOSIS AND SOLUTION (CONT)
The indoor fan speed is operating outside of the normal range (EH03)
Description: When the indoor fan speed remains too slow or too fast for an extended period of time, the LED displays a failure code and the
unit turns off.
Recommended parts to repair:
• Connection wires
• Indoor main PCB
• Fan assembly
• Indoor main PCB
Troubleshooting
Turn the power off. Wait 2 minutes, then restart.
Does a problem remain?
Shut off the power supply.
Rotate the fan by hand.
Check the fan motor wiring.
Is it improperly wired?
Measure the voltage for
the fan motor from the PCB.
Is it within normal parameters?
Replace the fan motor.
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
YES
Does it turn easily?
YES
YES
YES
NO The unit is operating normally.
NO
Find the cause of the problem and resolve.
Ensure the connections are good.
NO Replace the indoor main PCB.
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