Lennox LM009CI-100T432-1 Service Manual page 37

Display Method
No. Malfunction
of Indoor Unit
Name
(Error Code)
Overload
8 protection for
compressor
34
A/C Status
H3 The entire unit stops.
Possible Causes(For specific maintenance method, please
refer to the following procedure of troubleshooting)
1. Outdoor and indoor heat exchangers are too dirty or the air
inlet/outlet is blocked.
2. Fan motor is not working Abnormal fan speed; fan speed is
too low or the fan doesn't run.
3. Compressor doesn't work normally.Strange noise or leakage
occurs.Temperature of the shell is too high.
4. System is blocked inside(dirt block, ice block, oil block, Y-valve
not fully open).
5. High pressure switch is abnormal.
6. The refrigerant is leaking and cause overheating protection to
compressor.
Service Manual
Installation and Maintenance