Lennox LNIV2610 Service Manual page 18

9.2.2 Indoor and outdoor unit communication protection error
Turn off the power supply. After 1 minute, re-start
the unit using the remote control
The unit does not work normally
Check the wiring between the indoor and outdoor units.
Are the L, N, S & GND wires properly connected?
Yes
Are the LED4 (red) and LED1 (yellow) lights
blinking on the outdoor PCB?
No
The power supply for the outdoor PCB has failed.
Check the wiring on the outdoor PCB comparing it to
the wiring plate. Are the connections good?
No
Fix the connection.
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No
Re-connect and re-test
Yes
Replace indoor PCB
The unit does not
work normally
Yes
Replace the outdoor e-box
9.2.3 Fan speed has been out of control
Turn off the power supply and turn
it back on 5 secs later
The unit does not work normally
Turn off the unit and rotate the cross fan.
Does it rotate freely?
Yes
Is the fan motor connector and
connection good?
Yes
Is the voltage reaching the fan motor?
No
Replace the PCB
9.2.4 Open or short circuit of temperature sensor
Check the connections between the sensors
and the OCB. Are the connections good?
Yes
Replace the sensor and check if the error
re-occurs.
Disassemble the connection between
No
the fant and the motor. Check if the
bearing is normal. If not, change the
bearing. If OK, go to the next step.
Yes
Replace the fan motor
Yes
Replace the outdoor PCB
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