Midea MCH2U-18PHH2 Service Manual page 2

1. Indoor Unit Combination .................................................................................................................................... 4
2. Dimension Of Outdoor Unit ................................................................................................................................ 6
3. Refrigerant Cycle Diagram .................................................................................................................................. 7
4. Installation Details ............................................................................................................................................ 10
4.1 Wrench torque sheet for installation .......................................................................................................... 10
4.2 Connecting the cables ................................................................................................................................. 10
4.3 Pipe length and the elevation ..................................................................................................................... 10
4.4 First-Time Installation ................................................................................................................................. 11
4.5 Adding Refrigerant after Long-Term System Operation ............................................................................... 12
4.6 Procedure when servicing the indoor unit refrigeration circuit. ................................................................... 12
4.7 Evacuation after servicing the outdoor unit refrigeration circuit ................................................................. 14
6. Electronic Function ........................................................................................................................................... 15
6.1 Abbreviation ............................................................................................................................................... 15
6.2 Electric Control Working Environment. ....................................................................................................... 15
6.3 Main Protection .......................................................................................................................................... 15
6.4 Control and Functions ................................................................................................................................. 17
7. Wiring Diagrams ............................................................................................................................................... 23
8. Troubleshooting ............................................................................................................................................... 33
8.1Safety .......................................................................................................................................................... 33
8.2 Indoor Unit Error Display ............................................................................................................................. 34
8.3 Outdoor Unit Display .................................................................................................................................. 37
8.4 Diagnosis and Solution ................................................................................................................................ 42
8.5 Trouble Criterion Of Main Parts. ................................................................................................................. 91
9. Disassembly Instructions ................................................................................................................................ 103
 MCH2U-18PHH2 (WCA30 metal plate) .............................................................................................. 103
 MCH3U-27PHH2 (WD30 metal plate) ................................................................................................. 110
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