Lennox LICH4012021T431E-1, Руководство по обслуживанию

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Troubleshooting
Electrical Control System
124
2.4.1.5. Indoor Fan Speed Malfunction
Malfunction conditions When indoor fan speed continues to run at too low a speed (300RPM) for a
certain period of time, the unit will stop and the LED will display a failure
code.
Possible causes
●
Wiring mistakes
● Faulty fan assembly
●
Faulty fan motor
●
Faulty PCB
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 is operating normally
The unit is operating normally
Find the cause of the
problem and resolve it.
For example,
the fan may
be blocked or the screws
which fix the fan in place
are too tight
Find the cause of the
problem and resolve it.
For example,
the fan may
be blocked or the screws
which fix the fan in place
are too tight
Check the wiring of the fan
motor. Are all the
connections in working
order?
Check the wiring of the fan
motor. Are all the
connections in working
order?
No
Yes
No
Correct the connections
Correct the connections No
Replace the fan motor. Is the
problem resolved?
Replace the fan motor. Is the
problem resolved?
Yes
Yes
Replace the main PCB
Replace the main PCB No
Is the main PCB normally
operating according to index
1?
Is the main PCB normally
operating according to index
1?
Yes
No
Index 1:
1. Indoor DC fan motor (control chip is located inside the fan motor)
Power on and when the unit is on standby, measure the voltage of pin1-pin3, pin4-pin3 in the fan motor
connector. If the value of the voltage is not within the range shown in the following table, the PCB may be
experiencing problems and may need to be replaced.