Lennox LICH4012021T431E-1, Service Manual

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Electrical Control Function
Electrical Control System
117
If the indoor unit is not connected, the digital display shows:
“――”
27 Average of indoor room temperature
If the temperature is lower than 0
℃
, the digital display shows
“0”.
If the temperature is higher than 70
℃
, the digital display
shows “70”.
28 Shutdown cause Refer to Appendix
29 T2B of #1 indoor unit
If the temperature is lower than -9
℃
, the digital display shows
“9”.
If the temperature is higher than 70
℃
, the digital display
shows “70”.
If the capacity demand is 0, the digital display shows “0”.
If the indoor unit is not connected, the digital display shows:
“――”
30 T2B of #2 indoor unit
If the temperature is lower than 0
℃
, the digital display shows
“0”.
If the temperature is higher than 70
℃
, the digital display
shows “70”.
If the capacity demand is 0, the digital display shows “0”.
If the indoor unit is not connected, the digital display shows:
“――”
Appendix
Shutdown Causes Code
Frequency limit caused by current 1
Frequency limit caused by T2 in cooling 2
Frequency limit caused by T2 in heating 3
Preset temperature reached 4
Frequency limit caused by T4 5
Defrosting 6
Mode switching 7
High discharge temperature protection 9
High evaporator coil temperature T2 protection 10
Evaporator low temperature T2 protection 11
Condenser high temperature T3 protection
12
Low indoor room temperature protection in drying mode
13
Low
ambient
temperature protection
14
Refrigerant leakage detection 15
Communication malfunction between indoor and outdoor units 16
Communication error between outdoor main chip and compressor driven chip IR341 17
AC power input voltage protection 18
Top temperature protection of compressor 19
Outdoor EE Malfunction 20
Fan speed malfunction 21
Temperature sensor open or short circuit 22
Overcurrent protection 23
IMP overcurrent protection 24
Compressor lack of phase 25
Compressor malfunction 26
Low pressure protection of 311 27
Fan current protection 28
Fan lack of phase 29
Fan zero speed protection 30
PFC module protection 31
High pressure protection of 311 32
Zero speed malfunction 33
PWM malfunction 34
MCE malfunction 35