Lennox LICH4012021T431E-1, Service Manual

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Troubleshooting
Electrical Control System
121
T3 temperature sensor open or short circuit F2 O 3
T5 temperature sensor open or short circuit F3 O 4
Outdoor EEPROM malfunction (for some units) F4 O 5
Outdoor fan speed malfunction F5 O 6
T2B temperature open or short circuit (for free-match indoor units) F6 O 7
Communication error between auto-lifting panel and slim cassette F7 O 8
Auto-lifting panel is faulty (for slim cassettes with an auto-lifting panel) F8 O 9
Auto-lifting panel is not closed (for slim cassettes with an auto-lifting
panel)
F9 O 10
IPM module malfunction
P0 ☆ 1
DC voltage too high/too low protection P1 ☆ 2
High temperature protection of compressor top P2 ☆ 3
Low ambient temperature protection P3 ☆ 4
Inverter compressor drive protection P4 ☆ 5
Compressor low pressure protection P6 ☆ 7
Outdoor IGBT sensor is faulty P7
☆
8
O (on) X(off)
☆
(flash at 2Hz)
2.3
Outdoor Unit Malfunctions
For 18~60K:
Display Malfunction or Protection
E1 Communication malfunction between indoor and outdoor units
F0 Overcurrent protection
F1 Ambient temperature sensor (T4) malfunction
F2 Outdoor heat-exchanger temperature sensor (T3) malfunction
F3 Discharge temperature sensor (T5) malfunction
F4 Outdoor EEPROM malfunction
F5 Outdoor fan speed malfunction
P0
IPM module protection
P1 DC voltage too high/too low protection
P2 High temperature protection of compressor top
P3 Ultra-low ambient temperature protection
P4 Compressor rotor position protection
J0 Evaporator high temperature protection
J1 Condenser high temperature protection
J2 High discharge temperature protection
J3 PFC module protection
J4 Communication error between outdoor main chip and compressor driven chip
J5 High pressure protection
J6 Low pressure protection
P7 IGBT sensor malfunction
J8 AC power input voltage protection
In low ambient cooling mode, the LED displays “ LC ” or alternates between running frequency and “LC” (each
appears for 0.5s).