Lennox LI009HI-230P432, Service Manual

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Installation and Maintenance
Service Manual
(3) High temperature and overload protection diagnosis (AP1 hereinafter refers to the control board of the
outdoor unit)
Mainly detect:
●Is outdoor ambient temperature in normal range?
●Are the outdoor and indoor fans operating normally?
●Is the heat dissipation environment inside and outside the unit good?
Fault diagnosis process:
End
Y
N
Y
N
Y
N
Overheat and high
temperature protection
Is outdoor ambient temperature higher than 53?
20 minutes after the complete
unit is powered off.
Is heat dissipation of the indoor unit
and outdoor unit abnormal?
Normal protection, please operate
it after the outdoor ambient temp-
erature is normalized.
Improve the heat
dissipation environ-
ment of the unit
Does the outdoor fan work normally?
1. Check if the fan terminal OFAN
is connected correctly
2. Resistance between any two
terminals is measure by an ohm
gauge and should be less than 1K
Ohm.
Replace the
control panel AP1
Replace the fan
capacitor C1
Replace the
outdoor fan