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40MBAB: Service Manual
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
20
DIAGNOSIS AND SOLUTION (CONT.)
EH03 / EC07 - Fan Speed Is Operating Outside of Normal Range / EC 71 Over Current Failure of
Outdoor DC Fan Motor / EC73 Zero-speed failure of outdoor DC fan motor Diagnosis and Solution
Description: When the indoor / outdoor fan speed operates at too low or too high a speed for a certain time, the unit ceases
operation and the LED displays the failure.
Recommended parts to prepare:
• Connection wires
• Fan assembly
• Fan motor
• PCB
Troubleshooting and Repair:
NOTE: For certain models, the outdoor PCB cannot be removed separately. In this case, the outdoor electric control box should
be replaced as a whole.
YES
Power off. Restart the unit after 2 minutes.
Is it within normal parameters?
Replace the fan motor.
Does a problem remain?
The unit is operating normally.
NO
Shut off the power supply.
Rotate the fan by hand.
YES
Does it turn easily?
Inspect the unit for an obstruction and remove.
NO
Check the fan motor wiring.
YES
Is it improperly wired?
Ensure the proper connections.
Measure the voltage for
the fan motor from the PCB.
YES
Replace the main PCB.
NO