North American HVAC MOC-12HFN1-MS0W, Service Manual

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Troubleshooting
Electrical Control System 123
2.2 Indoor unit malfunction
For Console
NO. Malfunction Running lamp Timer lamp Defrosting lamp
1 Open or short circuit of T1 temperature sensor
☆
X X
2 Open or short circuit of T2 temperature sensor X X
☆
3
Communication malfunction between indoor and outdoor
units.
X
☆
X
4 Outdoor fan speed has been out of control X ☆ O
5 Indoor EEPROM malfunction
☆ ☆
X
6 IPM module protection
☆
X
☆
7
Open or short circuit of T3 or T4 temperature sensor or
Outdoor unit EEPROM parameter error
☆ ☆ ☆
8 Over voltage or over low voltage protection
☆ ☆
O
9 Top temperature protection of compressor ☆ O X
10 Inverter compressor drive protection
☆ ◎
X
11 Indoor fan Speed has been out of control.
☆
O ☆
O(light) X(off) ☆ (flash at 5Hz) ◎ (flash at 0.5Hz)
For 12K & 18K units(excluding console), MUE-24HRFN1-MW,MTB-24HRFN1-MW,MCD-24HRFN1-MW
NO. Malfunction
Running
lamp
Timer
lamp
Defrosting
lamp
Alarm
lamp
Display(nixie
tube)
1
Open or short circuit of T1 temperature
sensor
☆
X X X E0
2
Open or short circuit of T2 temperature
sensor
X X ☆ X E1
3
Communication malfunction between indoor
and outdoor units.
X
☆
X X E2
4 Water-level alarm malfunction X X X ☆ E3
5 Indoor EEPROM malfunction ☆ ☆ X X E4
6 IPM module protection ☆ X X O E5
7
Open or short circuit of T3 or T4 temperature
sensor or outdoor EEPROM is malfunction
☆ O X X E6
8 Outdoor fan speed has been out of control
☆
O
☆
X E7
9 Refrigerant Leakage Detection O X
☆ ☆
EC
10
Communication malfunction between main
PCB and up-down panel PCB
☆
X
☆ ☆
F0
11 Up-down panel malfunction X ☆ ☆ ☆ F1
12 Indoor fan speed has been out of control ☆ O O X F5
13 Outdoor unit voltage protection ☆ O X O P0
14 Compressor top temperature protection
☆
X O X P1
15 Outdoor unit over-current protection
☆ ☆ ☆
X P2
16 Inverter compressor drive error
☆ ◎
X X P4
O(light) X(off)
☆
(flash at 2.5Hz)
◎
(flash at 0.5Hz)
F0,F1 is only available for super-slim cassette