Mitsubishi Electric PUHY-HP200YNW-A Service Handbook page 186

Chapter 8

Troubleshooting Based on Observed Symptoms

8-1

MA Remote Controller Problems......................................................................................................... 1

8-1-1

The LCD Does Not Light Up. .................................................................................................................. 1

8-1-2

The LCD Momentarily Lights Up and Then Goes Off. ............................................................................ 2

8-1-3

"HO" and "PLEASE WAIT" Do Not Go Off the Screen. .......................................................................... 3

8-1-4

Air Conditioning Units Do Not Operate When the ON Button Is Pressed. .............................................. 4

8-2

ME remote Controller Problems .......................................................................................................... 5

8-2-1

The LCD Does Not Light Up. .................................................................................................................. 5

8-2-2

The LCD Momentarily Lights Up and Then Goes Off. ............................................................................ 6

8-2-3

"HO" or "Waiting for ···" Does Not Go Off the Screen............................................................................. 7

8-2-4

"88", "Request denied." Appears on the LCD. ........................................................................................ 9

8-3

Refrigerant Control Problems............................................................................................................ 10

8-3-1

Units in the Cooling Mode Do Not Operate at Expected Capacity........................................................ 10

8-3-2

Units in the Heating Mode Do Not Operate at Expected Capacity. ...................................................... 12

8-3-3

Outdoor Units Stop at Irregular Times. ................................................................................................. 14

8-4

Checking Transmission Waveform and for Electrical Noise Interference .................................... 15

8-4-1

M-NET................................................................................................................................................... 15

8-4-2

MA Remote Controller .......................................................................................................................... 17

8-5

Pressure Sensor Circuit Configuration and Troubleshooting Pressure Sensor Problems......... 18

8-5-1

Comparing the High-Pressure Sensor Measurement and Gauge Pressure......................................... 18

8-5-2

High-Pressure Sensor Configuration (63HS1)...................................................................................... 19

8-5-3

Comparing the Low-Pressure Sensor Measurement and Gauge Pressure.......................................... 20

8-5-4

Low-Pressure Sensor Configuration (63LS) ......................................................................................... 21

8-6

Troubleshooting Solenoid Valve Problems...................................................................................... 22

8-7

Troubleshooting Outdoor Unit Fan Problems.................................................................................. 24

8-8

Troubleshooting LEV Problems ........................................................................................................ 25

8-8-1

General Overview on LEV Operation.................................................................................................... 25

8-8-2

Possible Problems and Solutions ......................................................................................................... 28

8-8-3

Coil Removal Instructions ..................................................................................................................... 29

8-9

Troubleshooting Inverter Problems .................................................................................................. 31

8-9-1

Inverter-Related Problems and Solutions ............................................................................................. 31

8-9-2

Checking the Inverter Board Error Detection Circuit............................................................................. 33

8-9-3

Checking the Compressor for Ground Fault and Coil Resistance Problems ........................................ 33

8-9-4

Checking the Inverter for Damage at No-Load ..................................................................................... 34

8-9-5

Checking the Inverter for Damage during Compressor Operation........................................................ 35

8-9-6

Checking the Fan Motor for Ground Fault and Coil Resistance Problems ........................................... 36

8-9-7

Checking the Fan Board Error Detection Circuit at No Load ................................................................ 36

8-9-8

Checking the Fan Board for Damage at No Load................................................................................. 37

8-9-9

Checking the Fan Board for Damage with Load ................................................................................... 38

8-9-10 Checking the Installation Conditions..................................................................................................... 39

8-9-11 Solutions for the Main Breaker Trip ...................................................................................................... 39

8-9-12 Solutions for the Main Earth Leakage Breaker Trip .............................................................................. 40

8-9-13 Simple Check on Inverter Circuit Components ..................................................................................... 41

8-9-14 Troubleshooting Problems with IGBT Module ...................................................................................... 42

8-9-15 Checking the Fan Inverter Heatsink for Clogging ................................................................................. 44

8-10

Control Circuit..................................................................................................................................... 45

8-10-1 Control Power Supply Function Block................................................................................................... 45

8-10-2 Troubleshooting Problems with Outdoor Unit Transmission Power Supply Circuit .............................. 46

GB_BS_08_M

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