Midea M2OC-18HFN1-M Service Manual
  1. Manuals
  2. Brands
  3. Midea Manuals
  4. Air Conditioner
  5. M2OC-18HFN1-M
  6. Service manual

Midea M2OC-18HFN1-M Service Manual

Hide thumbs
Table of Contents

Advertisement

Quick Links

CONDENSING UNITS
Revision B:
Model Numbers:
M2OC-18HFN1-M
M2OD-18HFN1-M
M3OD-27HRDN1-M

Table of Contents

1.
Product Specifications
2.
3.
4.
5.
6.
7.
8.
Wiring Diagrams And Electrical Trouble Shooting
9.
10. Exploded View
WARNING
Installation MUST conform with local building codes or, in the absence of local
codes, with the National Electrical Code NFPA70/ANSI C1-1993 or current edition
and Canadian Electrical Code Part1 CSA C.22.1.
The information contained in the manual is intended for use by a qualified service
technician familiar with safety procedures and equipped with the proper tools and
test instruments
Installation or repairs made by unqualified persons can result in hazards to you
and others.
Failure to carefully read and follow all instructions in this manual can result in
equipment malfunction, property damage, personal injury and/or death.
Multi outdoor units
SERVICE MANUAL
ODMI-C1-1403
M3OC-30HRFN1-M
M4OC-36HRFN1-M
Multi zone

Advertisement

Table of Contents
loading

Related Manuals for Midea M2OC-18HFN1-M

Summary of Contents for Midea M2OC-18HFN1-M

  • Page 1: Table Of Contents

    Multi outdoor units Multi zone SERVICE MANUAL CONDENSING UNITS Revision B: ODMI-C1-1403 Model Numbers: M2OC-18HFN1-M M3OC-30HRFN1-M M2OD-18HFN1-M M4OC-36HRFN1-M M3OD-27HRDN1-M Table of Contents Product Specifications Indoor Unit Combination Suggested Indoor Unit Model Numbers Dimension Of Outdoor Unit Refrigerant Cycle Diagram Installation Details...
  • Page 2 9.1Safety ................................. 32 Indoor Unit Error Display ..........................33 9.3 Outdoor Unit Display ............................36 9.4 Diagnosis and Solution ............................. 40 9.5 Trouble Criterion Of Main Parts........................89 Disassembly Instructions ............................100  Model: M2OC-18HFN1-M, M2OD-18HFN1-M (W210 metal plate) ..........100...
  • Page 3  Model: M3OD-27HRDN1-M (W210 metal plate) ................. 106  Model: M3OC-30HRFN1-M (W310 metal plate).................. 113  Model: M4OC-36HRFN1-M (W520 metal plate).................. 121...

  • Page 4: Indoor Unit Combination

    1. Indoor Unit Combination 7+9+12 7+9+18 Multi DC Nominal Suggested 7+12+12 Limit Outdoor Unit capacity Combination 9+9+9 9+9+12 9+12+12 1drive 2(M2OC) 5.2kW None 7+12 Multi DC Nominal Suggested Limit Outdoor Unit capacity Combination 9+12 Multi DC Nominal Suggested Limit Outdoor Unit capacity Combination 7+12...
  • Page 5 9+9+12+18 9+12+12+12 7+12 9+12+12+18 7+18 12+12+12+12 9+12 9+18 12+12 12+18 18+18 7+7+7 7+7+9 7+7+12 7+7+18 7+9+9 7+9+12 7+9+18 7+12+12 7+12+18 9+9+9 9+9+12 9+9+18 9+12+12 9+12+18 9+18+18 12+12+12 12+12+18 12+18+18 7+7+7+7 7+7+7+9 7+7+7+12 7+7+7+18 7+7+9+9 7+7+9+12 7+7+9+18 7+9+9+9 7+9+9+12 7+9+9+18 7+9+12+12 7+9+12+18 7+12+12+12 7+12+12+18...

  • Page 6: Suggested Indoor Unit Model Numbers

    3. Suggested Indoor Unit Model Numbers SUGGESTED INDOOR MS9AI-07HRDN1-M SUGGESTED INDOOR MS9AI-07HRDN1-M MS9AI-09HRDN1-M(A) MSV1I-09HRDN1-M MS9AI-09HRDN1-M(A) MS11M-09HRFN1-MX4W MSV1I-09HRDN1-M MS11M-09HRFN1-MW0W MSV1I-12HRDN1-M MSV1I-12HRDN1-M MS9AI-12HRDN1-M MS9AI-12HRDN1-M MS11M-12HRFN1-MV0W MTBI-12HWDN1-M MS11M-12HRFN1-MW0W MTBU-12HRDN1-M MTBI-12HWDN1-M MFAI-12HRDN1-M MTBU-12HRDN1-M MFAU-12HRFN1-M MFAI-12HRDN1-M MCA2I-12HRDN1-M MFAU-12HRFN1-M MCA2U-12HRFN1-M MCA2I-12HRDN1-M MUBI-12HRDN1-M MCA2U-12HRFN1-M MUBU-12HRFN1-M MUBI-12HRDN1-M MUBU-12HRFN1-M MSV1I-18HRDN1-M SUGGESTED INDOOR MS9AI-18HRDN1-M...

  • Page 7: Dimension Of Outdoor Unit

    4. Dimension Of Outdoor Unit Dimension (mm(in.)) Model M2OC-18HFN1-M M2OD-18HFN1-M 845(33.3) 320(12.6) 700(27.6) 908(35.7) 560(22) 335(13.2) M3OD-27HRDN1-M M3OC-30HRFN1-M 900(35.4) 315(12.4) 860(33.9) 980(38.6) 590(23.2) 333(13.1) M4OC-36HRFN1-M 990(39) 345(13.6) 965(38) 1075(42.3) 624(24.6) 366(14.4)

  • Page 8: Refrigerant Cycle Diagram

    5. Refrigerant Cycle Diagram 5.1Refrigeration circuit drawing of inverter dual zone INDOOR OUTDOOR EXV A CAPILIARY A LIQUID VALVE A CHECK VALVE EXV B CAPILIARY B LIQUID VALVE B Condenser temp. sensor CAPILIARY TUBE HEAT HEAT EXCHANGE T4 Ambient T1 Room EXCHANGE (EVAPORATOR) temp.

  • Page 9: Installation Details

    6. Installation Details When using the extension pipe, refer to the tables below. 6.1 Wrench torque sheet for installation ● When refrigerant pipe diameter is different from that of outdoor unit union (for 18K indoor Outside diameter Torque Additional tightening torque unit), additional transfer connector needs to inch N.cm...
  • Page 10 Procedure: 1). Confirm that both the 2-way and 3-way valves are set to the closed position. 1. Completely tighten the flare nuts of the indoor 2). Connect the charge set and a charging cylinder and outdoor units, confirm that both the 2-way to the service port of the 3-way valve.

  • Page 11: Adding The Refrigerant After Running The System For Many Years

    6.5 Adding the refrigerant after running the system for many years Procedure: 1). Connect the charge hose to the charging Procedure cylinder, open the 2-way valve and the 3-way 1). Connect the charge hose to the 3-way service valve. port, open the 2-way valve and the 3-way valve. Connect the charge hose which you disconnected Connect the charge hose to the valve at the from the vacuum pump to the valve at the bottom...

  • Page 12: Re-Installation While The Outdoor Unit Need To Be Repaired

    to the service port of the 3-way valve Leave the valve on the charging cylinder closed. 3). Air purging. Open the valves on the charging cylinder and the charge set. Purge the air by loosening the flare nut on the 2-way valve approximately 45’ for 3 seconds then closing it for 1 minute;...

  • Page 13: Electronic Function

    turn off the vacuum pump, and confirm that the gauge needle does not move (approximately 5 minutes after turning off the vacuum pump). 7. Electronic Function 5). Disconnect the charge hose from the vacuum pump. 7.1 Abbreviation 2. Refrigerant charging T1: Indoor ambient temperature T2: Coil temperature of indoor heat exchanger middle.
  • Page 14 ---- When outdoor fan speed is lower than COOL_F5 ICOOLLMT1 300RPM or higher than 2400RPM for 60 second, If the current frequency is lower than COOL_F4, the frequency will the whole unit stops and LED displays failure. not be limited. After 10s of the compressor start, if the current>ICOOL, the AC will display the failure for 30 seconds and stop.

  • Page 15: Control And Functions

    1.If the compressor frequency keeps lower than RET_OIL_FREQ1_ADD for RET_OIL_TIME1_ADD,the AC will rise the T1 Ts frequency to RET_OIL_FREQ2_ADD for RET_OIL_TIME2_ADD and then resume to former frequency. 2.During the oil return process, the EXV will keep 300p while the indoor units will keep the current running mode.
  • Page 16 When there’re more than one indoor unit Meanwhile the maximum running frequency will be adjusted according to the outdoor ambient temp. Outdoor temperature (T4) Heating ≥17℃ ＜0℃ ＜12℃ 12℃ ~ 17℃ Modify rate 120% 100% T4LimFre5_ADD Note: The final result is integer. Then modify it according to T2 T4LimFre4_ADD average(correction):...
  • Page 17 Defrosting action： 4-way valve defrosting Defrosting over low ambient cooling compressor Max 10 minutes frequency Cool-F9 frequency Compressor stops For M2OC-18HFN1-M, M2OD-18HFN1-M,M3OC- TimeA 30HRFN1-M, M4OC-36HRFN1-M: 10S 30S Indoor fan Anti-cold control Outdoor fan DC_FAN_HI_SPD_ADD 28℃ EXV open 26℃ 480P...
  • Page 18 100-350p.. When the unit start to work for 3minutes, the outdoor will receive indoor units( of capacity demand) T2 information and calculate the average of them. After comparing For M2OC-18HFN1-M,M2OD-18HFN1-M,M3OC- each indoor’s T2 with the average, the outdoor 30HRFN1-M, M4OC-36HRFN1-M: gives the following modification commands: If the T2＞average+2, the relevant valve needs...

  • Page 19: Wiring Diagrams

    8. Wiring Diagrams 8.1 Wiring diagram of 1 drive 2 outdoor M2OC-18HFN1-M, M2OD-18HFN1-M...
  • Page 20 PCB board of M2OC-18HFN1-M, M2OD-18HFN1-M...
  • Page 21 IPM board of M2OC-18HFN1-M...
  • Page 22 IPM board of M2OD-18HFN1-M...
  • Page 23 8.2 Wiring diagram of 1 drive 3 outdoor M3OD-27HRDN1-M M3OC-30HRFN1-M...
  • Page 24 PCB board of M3OC-30HRFN1-M...
  • Page 25 IPM board of M3OC-30HRFN1-M...
  • Page 26 PCB board of M3OD-27HRDN1-M...
  • Page 27 IPM board of M3OD-27HRDN1-M...
  • Page 28 8.3 Wiring diagram of 1 drive 4 outdoor M4OC-36HRFN1-M...
  • Page 29 PCB board of M4OC-36HRFN1-M...
  • Page 30 IPM board of M4OC-36HRFN1-M...
  • Page 31 PFC board of M4OC-36HRFN1-M...

  • Page 32: Troubleshooting

    9. Troubleshooting 9.1Safety Because of there are capacitors in PCB and relative circuit in outdoor unit, even shut down the power supply, electricity power still are kept in capacitors, do not forget to discharge the electricity power in capacitor. The value of resistance is about 1500 ohm to 2000 ohm Electrolytic Capacitors (HIGH VOLTAGE! CAUTION!) Bulb (25-40W)

  • Page 33: Indoor Unit Error Display

    9.2 Indoor Unit Error Display Vertu series & Luna series: ODU Error code Display Failure —— Indoor EEPROM malfunction Communication malfunction between indoor and outdoor units —— Zero-crossing signal error Indoor fan speed has been out of control —— E0,E4 Open circuit or short circuit of outdoor temperature sensor or outdoor EEPROM malfunction ——...
  • Page 34 For MCA2I-12HRDN1-M, MCA2I-18HRDN1-M, MUBI-12HRDN1-M, MUBI-18HRDN1-M: Operation Timer De-frost Alarm Failure ★ Open or short circuit of T1 temperature sensor ★ Open or short circuit of T2 temperature sensor ★ Communication malfunction between indoor and outdoor units ★ Full-water malfunction ★ ★...
  • Page 35 For MTBU-12HRDN1-M, MTBU-18HRDN1-M, MCA2U-12HRFN1-M, MCA2U-18HRFN1-M, MUBU- 12HRFN1-M, MUBU-18HRFN1-M: ODU Error Operatio Display Timer De-frost Alarm Failure code —— ★ Open or short circuit of T1 temperature sensor —— ★ Open or short circuit of T2 temperature sensor Communication malfunction between indoor and ★...

  • Page 36: Outdoor Unit Display

    ★ 1 times ★ Inverter module (IPM) malfunction or IGBT over-strong current protection ★ 2 times ★ Voltage(High voltage or low voltage ) protection. ★ 3 times ★ High temperature protection of compressor top (only for M3OD-27HRDN1-M) —— ★ 5 times ★...
  • Page 37 Display Remark Normal display Display running frequency, running state or malfunction code No. of indoor units in good connection Actual data Display Number of indoor unit Outdoor unit running mode code Off:0,Fan only 1, Cooling:2, Heating:3, Forced cooling:4 A indoor unit capacity B indoor unit capacity The capacity unit is horse power.
  • Page 38 AD value of current The display value is hex number. For example ,the digital display tube show “Cd”, it means AD value is 205. AD value of voltage EXV open angle for A indoor unit EXV open angle for B indoor unit Actual data/4.
  • Page 39 9.3.3 Outdoor unit error display Display LED STATUS Error Error Error (MTBI(MTBU)) (Vertu/Luna) (Oasis) Outdoor EEPROM malfunction Communication malfunction between indoor and outdoor units Communication malfunction between IPM board and outdoor main —— —— —— board Open or short circuit of outdoor temperature sensor(T3、T4、TP、 T2B) Voltage protection ——...

  • Page 40: Diagnosis And Solution

    9.4 Diagnosis and Solution 9.4.1 Indoor unit trouble shooting 9.4.1.1 Indoor EEPROM malfunction diagnosis and solution. Malfunction decision PCB main chip does not receive feedback from EEPROM chip conditions ● Installation mistake ● PCB faulty Trouble shooting: Shut off the power supply and turn it on 1 minute later.
  • Page 41 9.4.1.2 Communication malfunction between indoor and outdoor units diagnosis and solution. Malfunction decision Indoor unit does not receive the feedback from outdoor unit conditions during 120 seconds. ● Wiring mistake Supposed causes ● Indoor or outdoor PCB faulty Trouble shooting:...
  • Page 42 Indoor / outdoor units communication error Start: Power off , then Power on the A/C by the Breaker. (reconnect the power wire). Is it still displaying the error code? Check wiring on the outdoor and indoor terminal follow the wiring diagram. Is all Reconnect the wiring connecting correctly? Reconnect the wiring...
  • Page 43 Pic 1:Use a multimeter to test the DC voltage between L2 port and S port of outdoor unit. The red pin of multimeter connects with L2 port while the black pin is for S port. When AC is normal running, the voltage will move alternately between positive value and negative value.
  • Page 44 PIC3 :Main board LED when power on and unit standby. PIC 4: Check point button, press 1 time for check how many indoor units are connected.(for M2OC- 18HFN1-M, M2OD-18HFN1-M,M3OD-27HRDN1- M,M3OC-30HRFN1-M,M4OC-36HRFN1-M) Check point button, press 18 times for check how many indoor units are connected.(for M2OC- 18HRDN1-M,M3OC-27HRDN1-M,M4OC-36HRDN1-...
  • Page 45 9.4.1.3 zero-crossing signal error diagnosis and solution. Malfunction decision When PCB does not receive zero crossing signal feedback for conditions 4 minutes or the zero crossing signal time interval is abnormal. ● Connection mistake Supposed causes ● PCB faulty Trouble shooting: Check if the connections and Correct the connections.
  • Page 46 9.4.1.4 Indoor fan speed has been out of control diagnosis and solution. Malfunction decision When indoor fan speed keeps too low (300RPM) for certain time, the unit conditions will stop and the LED will display the failure. ● Wiring mistake Supposed causes ●...
  • Page 47 Index 1: 1.Indoor AC fan motor Measure the resistance value of each winding by using the tester. For the definite value of the resistance, refer to 9.5 Trouble Criterion Of Main Parts  2. Indoor DC fan motor(control chip is inside fan motor) Measure the resistance value of each winding by using the tester.
  • Page 48 Color Black White Yellow Blue Index2: 1: Indoor AC fan motor Power on and set the unit running in fan mode at high fan speed. After running for 15 seconds, measure the voltage of pin1 and pin2. If the value of the voltage is less than 100V(208~240V power supply)or 50V(115V power supply), the PCB must have problems and need to be replaced.
  • Page 49 For console: DC motor voltage input and output For light commercial(except console): Color Signal Voltage Vs/Vm 192V~380V Black White 13.5-16.5V Yellow 0~6.5V Blue For console: Color Signal Voltage 310V White Blue Yellow 0-7.5V Black...
  • Page 50 9.4.1.5 open or short circuit of temperature sensor diagnosis and solution. Malfunction decision If the sampling voltage is lower than 0.06V or higher than conditions 4.94V, the LED will display the failure. ● Wiring mistake Supposed causes ● Sensor faulty ●...
  • Page 51 9.4.1.6 IPM module or IGBT over-strong current protection diagnosis and solution. Malfunction decision When the voltage signal that IPM send to compressor drive chip is abnormal, the display LED will show “P6” and AC will conditions turn off. ● Wiring mistake Supposed causes ●...
  • Page 52 IPM module protection Check whether the voltage range Check whether the input Regulate it to correct, then of P-N on IPM module is normal? power supply is correct? check whether the system DC277-356V for 18-27KBtu/h; 208-230V, 1N, 60Hz can work normally? DC277-410V for 36KBtu/h Check whether the connecting Connect it tightly,...
  • Page 53 9.4.1.7 Over voltage or too low voltage protection diagnosis and solution. Voltage protection Check the voltage of outdoor unit power supply, whether the voltage Check the power supply between L(L1) and N (L2) is about 187~253VAC Check whether the voltage of IPM board P and N is normal? DC277-356V for 18-27KBtu/h;...
  • Page 54 9.4.1.8 Temperature protection of compressor top diagnosis and solution. Malfunction decision If the sampling voltage is not 5V, the LED will display the conditions failure. ● Wiring mistake Supposed causes ● Over load protector faulty ● System block ● Outdoor PCB faulty Temperature protection of compressor top Whether compressor...
  • Page 55 Full-water malfunction (For cassette/A5 duct) 9.4.1.10 diagnosis and solution Malfunction decision If the sampling voltage is not 5V, the LED will display the conditions failure. ● Wiring mistake Supposed causes ● Water-level switch faulty ● Water pump faulty ● Indoor PCB faulty If the water-level switch Insert the water-level switch well is inserted well?
  • Page 56 9.4.1.11 Mode conflict. Error Code Malfunction decision The indoor units cannot work cooling mode and heating at same time. conditions Heating mode has a priority. ● Suppose Indoor unit A working in cooling mode or fan mode, and Unit action indoor unit B is set to heating mode, then A will change to off and B will work in heating mode.
  • Page 57 9.4.2 Outdoor unit trouble shooting 9.4.2.1 E0(Outdoor EEPROM malfunction) error diagnosis and solution Error Code Malfunction decision PCB main chip does not receive feedback from EEPROM chip conditions ● Installation mistake Supposed causes ● PCB faulty Trouble shooting: Outdoor EEPROM malfunction If the EEPROM chip is welded on PCB, replace the PCB...
  • Page 58 9.4.2.2 E2(Communication malfunction between indoor and outdoor units) error diagnosis and solution. Error Code Malfunction decision Indoor unit does not receive the feedback from outdoor unit conditions during 120 seconds or outdoor unit does not receive the feedback from any one indoor unit during 180 seconds. ●...
  • Page 59 Indoor / outdoor units communication error Start: Power off , then Power on the A/C by the Breaker. (reconnect the power wire). Is it still displaying the error code? Check wiring on the outdoor and indoor terminal follow the wiring diagram. Is all Reconnect the wiring connecting correctly? Reconnect the wiring...
  • Page 60 Pic 1:Use a multimeter to test the DC voltage between L2 port and S port of outdoor unit. The red pin of multimeter connects with L2 port while the black pin is for S port. When AC is normal running, the voltage will move alternately between positive value and negative value.
  • Page 61 Pic 2: :IPM (For qua-zone) Power, Self-Check Operating PIC3 :Main board LED when power on and unit standby. PIC 4: Check point button, press 1 time for check how many indoor units are connected.
  • Page 62 9.4.2.3 E3(Communication malfunction between IPM board and outdoor main board) error diagnosis and . Error Code Malfunction decision PCB main chip does not receive feedback from IPM module conditions during 60 seconds. ● Wiring mistake Supposed causes ● PCB faulty Trouble shooting: Communication malfunction between IPM board and outdoor main board...
  • Page 63 Remark: Use a multimeter to test the DC voltage between black pin and white pin of signal wire The normal value should be around 5V. Use a multimeter to test the DC voltage between black pin and red pin of signal wire. The normal value should be around 12V.
  • Page 64 9.4.2.4E4(open or short circuit of outdoor temperature sensor) diagnosis and solution F1/F2/F3/F4/F5 (open or short circuit of indoor coil temperature sensor) diagnosis and solution. Error Code E4/F1/F2/F3/F4/F5 Malfunction decision If the sampling voltage is lower than 0.06V or higher than conditions 4.94V, the LED will display the failure.
  • Page 65 9.4.2.5 E5(Voltage protection) error diagnosis and solution. Error Code Malfunction decision An abnormal voltage rise or drop is detected by checking the conditions specified voltage detection circuit. ● Power supply problems. Supposed causes ● System leakage or block ● PCB faulty Trouble shooting: Voltage protection Check the voltage of...
  • Page 66 IPM (for dual/tri- zone) IPM (for qua- zone) P-N (for dual/tri-zone)
  • Page 67 P-N (for qua-zone)
  • Page 68 bridge rectifier (for dual/tri-zone) bridge rectifier (for qua-zone)
  • Page 69 Remark: Measure the DC voltage between + and - port. The normal value should be 190V~250V.
  • Page 70 9.4.2.6 E6(PFC module protection) error diagnosis and solution. (Only for M4OC-36HRFN1-M) Error Code Malfunction decision When the voltage signal that PFC sends to main control board is abnormal, the display LED will show “E6” and AC will turn conditions off. Supposed causes ●...
  • Page 71 Inductance Two ports of the inductance...
  • Page 73 9.4.2.7 E8(Outdoor fan speed has been out of control) diagnosis and solution(Only for DC fan motor models). Error Code Malfunction decision When outdoor fan speed keeps too low (300RPM) or too high(2400RPM) conditions for certain time, the unit will stop and the LED will display the failure. ●...
  • Page 74 Index 1: 1. DC fan motor(control chip is inside fan motor) Measure the resistance value of each winding by using the tester. If any resistance value is zero, the fan motor must have problems and need to be replaced. Color Black White Yellow...
  • Page 75 DC motor voltage input and output Color Signal Voltage Vs/Vm 140~380V(M4OC-36HRFN1-M) 263~400V(M2OC-18HFN1-M M2OD-18HFN1-M) 192~380V(M3OC-30HRFN1-M) Black White 13.5~16.5V Yellow 0~6.5V Blue...
  • Page 76 9.4.2.8 P0(Temperature protection of compressor top) error diagnosis and solution. (Only for M3OD- 27HRDN1-M) Error Code If the sampling voltage is not 5V, the LED will display the failure. Malfunction decision conditions ● Wiring mistake Supposed causes ● Over load protector faulty ●...
  • Page 78 9.4.2.9 P1(High pressure protection) error diagnosis and solution. (Only for M4OC-36HRFN1-M) Error Code Malfunction decision If the sampling voltage is not 5V, the LED will display the conditions failure. ● Wiring mistake Supposed causes ● Over load protector faulty ● System block ●...
  • Page 80 9.4.2.10 P2(Low pressure protection) error diagnosis and solution. (Only for M4OC-36HRFN1-M) Error Code Malfunction decision If the sampling voltage is not 5V, the LED will display the conditions failure. ● Wiring mistake Supposed causes ● Over load protector faulty ● System block ●...
  • Page 82 9.4.2.11 P3(Current protection of compressor) error diagnosis and solution. Error Code Malfunction decision If the compressor current exceeds the current limit value for conditions 10 seconds, the LED will display the failure. ● Wiring mistake Supposed causes ● Over load protector faulty ●...
  • Page 84 9.4.2.12 P4(Temperature protection of compressor discharge) error diagnosis and solution. Error Code Malfunction decision When the compressor discharge temperature(Tp) is more conditions than 115℃ for 10 seconds, the compressor will stop restart till Tp is less than 90℃. ● Refrigerant leakage Supposed causes ●...
  • Page 85 9.4.2.13 P5(High temperature protection of condenser) error diagnosis and solution. Error Code When outdoor pipe temperature is more than 65° C, the unit will Malfunction decision stop, and unit runs again when outdoor pipe temperature is less conditions than 52° C ●...
  • Page 86 9.4.2.14 P6(IPM module protection) error diagnosis and solution. Error Code Malfunction decision When the voltage signal that IPM send to compressor drive chip is abnormal, the display LED will show “P6” and AC will conditions turn off. ● Wiring mistake Supposed causes ●...
  • Page 87 IPM module protection Check whether the voltage range Check whether the input Regulate it to correct, then of P-N on IPM module is normal? power supply is correct? check whether the system DC277-356V for 18-27KBtu/h; 208-230V, 1N, 60Hz can work normally? DC277-410V for 36KBtu/h Check whether the connecting Connect it tightly,...
  • Page 88 9.4.2.15 The cooling operation or heating operation does not operate. ● 4-way valve faulty Supposed causes Check of 4-way, please refer to part 5 in 9.5 Trouble Criterion Of Main Parts. 9.4.2.16 When cooling, heat exchanger of non-operating indoor unit frosts. When heating, non-operating indoor unit get warm.

  • Page 89: Trouble Criterion Of Main Parts

    Model MUBI-12HRDN1-M MUBI-18HRDN1-M MUBU-12HRFN1-M MUBU-18HRFN1-M Indoor fan motor YSK25-6L YSK25-6L WZDK55-38GS-W WZDK55-38GS-W Model MFAI-12HRDN1-M MFAU-12HRFN1-M Indoor fan motor RD-280-20-8A RD-280-20-8A Outdoor unit Model M3OD-27HRDN1-M M3OC-30HRFN1-M M4OC-36HRFN1-M M2OC-18HFN1-M M2OD-18HFN1-M Compressor DA130S1C-20FZ DA150S1C-20FZ DA250S2C-30MT TNB306FPGMC-L Outdoor fan motor WZDK50-38G YDK53-6FB(B) WZDK72-38G WZDK180-38G...
  • Page 90 1.Temperature sensor checking Disconnect the temperature sensor from PCB, measure the resistance value with a tester. Temperature Sensors. Room temp.(T1) sensor, Indoor coil temp.(T2) sensor, Outdoor coil temp.(T3) sensor, Outdoor ambient temp.(T4) sensor, Compressor discharge temp.(Tp) sensor. Measure the resistance value of each winding by using the multi-meter.
  • Page 91 Appendix 1 Temperature Sensor Resistance Value Table (℃--K) ℃ ℃ ℃ ℃ K Ohm K Ohm K Ohm K Ohm 115.266 12.6431 2.35774 0.62973 108.146 12.0561 2.27249 0.61148 101.517 11.5000 2.19073 0.59386 96.3423 10.9731 2.11241 0.57683 89.5865 10.4736 2.03732 0.56038 84.2190 10.000 1.96532...
  • Page 92 Appendix 2 Unit: ℃---K Discharge temp. sensor table 542.7 68.66 13.59 3.702 511.9 65.62 13.11 3.595 62.73 12.65 3.492 455.9 59.98 12.21 3.392 430.5 57.37 11.79 3.296 406.7 54.89 11.38 3.203 384.3 52.53 10.99 3.113 363.3 50.28 10.61 3.025 343.6 48.14 10.25 2.941...
  • Page 93 Appendix 3: ℃ 10 11 12 13 14 15 16 17 18 19 20 21 22 ℉ 48 50 52 54 56 58 60 62 64 66 68 70 72 ℃ 23 24 25 26 27 28 29 30 31 32 33 34 35 ℉...
  • Page 94 3.IPM continuity check Turn off the power, let the large capacity electrolytic capacitors discharge completely, and dismount the IPM. Use a digital tester to measure the resistance between P and UVWN; UVW and N. Normal Normal resistance Digital tester Digital tester resistance value value...
  • Page 95 Position Resistance Value YDK53- YDK70-6FB YDK180-8GB YSK27-4G YSK68-4B YDK45-6B YSK25-6L 6FB(B) 56Ω± 8% 24.5Ω± 8% 317Ω± 8% 145Ω± 8% 345Ω± 8% 627Ω± 8% 88.5Ω± 8% Black - (20℃) (20℃) (20℃) (20℃) (20℃) (20℃) (20℃) 76Ω± 8% 19Ω± 8% 252Ω± 8% 88Ω±...
  • Page 96 6.EXV check Disconnect the connectors.
  • Page 97 Resistance to EXV coil Color of lead wire Normal Value Red- Blue Red - Yellow About 50Ω Brown-Orange Brown-White...
  • Page 98 Red- Blue Red - Yellow...
  • Page 99 Brown-Orange Brown-White...

  • Page 100: Disassembly Instructions

    10. Disassembly Instructions  Model: M2OC-18HFN1-M, M2OD-18HFN1-M (W210 metal plate) Part name Procedures Remarks How to remove the panel plate. Screws of top cover Panel plate 1) Stop operation of the air conditioner and turn “OFF” the power breaker. Screws of front panel...
  • Page 101 5) Remove the screws of big handle, and remove the big Screws of handle.(4 screws) big handle 6) Remove two screws of terminal board, four screws of water collector and Screws of water collector fourteen screws of right- rear panel, and remove the Screws of right-rear panel.
  • Page 102 4) Remove the electrical ④ control box cover. 5) Disconnect the fan motor connector CN37(5p,white) from the PCB board. ⑤ Remove the fan motor after unfastening four fixing screws. ⑥ How to remove the electrical Electrical ③ parts. parts 1) Perform work of item 1,2. 2) Remove the ten screws fixing the IPM board.
  • Page 103 CN38(2p,white) CN21(5p,white) CN39(2p,blue) L-OUT(red) N-OUT(blue) CN17 Remove the IPM board. CN15 Disconnect the connectors and wires connected from PCB and other parts. Connectors: CN18/CN19 CN25/CN23 CN17:T3/T4 temp. sensor (2p/2p,white) CN7: Tdischarge temp. sensor (2p,white) CN15:T2B-A,B temp. sensor (2p/2p,white) CN18/CN19: Electronic expansive valve A,B (6p/6p,red/red) CN25/CN23: S-A,S-B CN5/CN6...
  • Page 104 Disconnect the grounding ⑧ wire (yellow-green) after removing the big handle and the right-rear panel. Remove the PCB board. How to remove the compressor. Compressor 1) Perform work of item 1,2,3. 2) Remove the electrical control box and partition plate. 3) Extract refrigerant gas.
  • Page 105 Reactor How to remove the reactor 1) Perform work of item 1,2 2) Unfasten the connector between IPM and reactor. 3) Remove two screws of cover of inductance, and remove the cover of inductance Screws of cover of inductance 4) Disconnect two pieces of wires connected from the cover of inductance.
  • Page 106  Model: M3OD-27HRDN1-M (W210 metal plate) Part name Procedures Remarks How to remove the panel plate. Panel plate Screws of top cover 1) Stop operation of the air conditioner and turn “OFF” the power breaker. 2) Remove the screws of top cover, and remove the top cover.
  • Page 107 Screws of big handle Screws of right-rear panel Screws of water collector Screws of terminal board How to remove the fan ass’y. Fan ass’y 1) Remove the top cover, right front side panel and front panel from item 1.step 1~4 2) Remove the hex nut fixing ②...
  • Page 108 ④ 5) Disconnect the fan motor connector CN11(5p,white) from the PCB board. ⑤ 6) Remove the fan motor after unfastening six fixing screws. Note: There are two kinds of screws. Please pay attention to it when install the fan motor. ⑥...
  • Page 109 Disconnect following 3 pieces of connection wires and connectors between IPM and PCB. CN21(5p,white) L-OUT(red) N-OUT(blue) Remove the IPM board. ⑥ CN18/CN19/CN22 CN17 Disconnect connectors and wires connected from PCB and other parts. Connectors: CN17:T3/T4 temp. sensor (2p/2p,white) CN7: Tdischarge temp. sensor (2p,white) CN12:Ttop temp.
  • Page 110 CN4:L2-IN (black) Disconnect the grounding wire (yellow-green) CN20/ CN23/ after removing the big handle CN25 and the right-rear panel. Remove the PCB board. CN1/CN2 CN5/CN6 ⑧ How to remove the compressor. Compressor 1) Perform work of item 1,2,3. 2) Remove electrical control box and partition plate.
  • Page 111 washers fixing compressor to bottom plate. ⑦ 8) Lift the compressor. Reactor How to remove the reactor 1) Perform work of item 1,2 2) Unfasten connector between IPM and reactor. 3) Remove screws cover of inductance, and remove cover inductance Screws of cover of inductance...
  • Page 112 How to remove the expansion expansion valve valve 1) Perform work of item 1,2. 2) Remove the electrical parts from item 3. Expansion valves 3) Remove the coils. 4) Detach the welded parts of . Coils expansion valves and pipes.
  • Page 113  Model: M3OC-30HRFN1-M (W310 metal plate) Part name Procedures Remarks How to remove the panel plate. Screws of top cover Panel plate 1) Stop operation of the air conditioner and turn “OFF” the power breaker. 2) Remove the screws of top cover, and remove the top cover.
  • Page 114 Screws of top cover Screws of right- rear panel Screws of front panel...
  • Page 115 How to remove the fan ass’y. Fan ass’y 1) Remove the top cover, right front side panel and front panel from item 1.step 1~4 2) Remove the hex nut fixing ② the fan. 3) Remove the fan. ④ 4) Remove electrical control box cover.
  • Page 116 Disconnect following 5 ④ pieces of connection wires and connectors between IPM and PCB. L-OUT(red) N-OUT(blue) CN38(2p,white) CN21(5p,white) CN39(2p,blue)
  • Page 117 Remove the IPM board. ⑥ 7) Disconnect the connectors and wires connected from PCB and other parts. Connectors: CN17:T3/T4 temp. sensor (2p/2p,white) CN7: Tdischarge temp. sensor CN17 (2p,white) CN15:T2B-A,B,C temp. sensor (2p/2p/2p,white) CN18/CN19/CN22: Electronic expansive valve A,B,C (6p/6p/6p,red/red/red) CN25/CN23/CN20: S-A,S-B,S-C (3p/3p/3p,white/white/white) CN15 CN18/CN19/CN22...
  • Page 118 ⑧ How to remove the compressor. Compressor 1) Perform work of item 1,2,3. 2) Remove electrical control box and partition plate. 3) Extract refrigerant gas. 4) Remove sound ⑥ insulation material crankcase heating cable. 5) Remove terminal cover of compressor, and disconnect wires of compressor thermo and compressor from the terminal.
  • Page 119 Reactor How to remove the reactor Screws of cover of inductance 1) Perform work of item 1,2 2) Unfasten the connector between IPM and reactor. 3) Remove four screws cover of inductance, and remove cover inductance 4) Disconnect two pieces of wires connected from the cover of inductance.
  • Page 120 How to remove the expansion expansion valve valve 1) Perform work of item 1,2. 2) Remove the electrical parts from item 3. Expansion 3) Remove the coils. valves 4) Detach the welded parts of expansion valves and pipes. . Coils...
  • Page 121  Model: M4OC-36HRFN1-M (W520 metal plate) Part name Procedures Remarks How to remove the panel plate. Screws of top cover Panel plate 1) Stop operation of the air conditioner and turn “OFF” the power breaker. Screws of front panel Screws of right front side panel 2) Remove the screws of top Screws of top cover cover, and remove the top...
  • Page 122 Screws of big handle Screws of right- rear panel Screws of water collector Screws of terminal board...
  • Page 123 How to remove the fan ass’y. Fan ass’y 1) Remove the top cover, right front side panel and front panel from item 1.step 1~4 ② 2) Remove the hex nut fixing the fan. 3) Remove the fan. 4) Remove the electrical control box cover after remove 5 screws.
  • Page 124 ③ 4) Disconnect following connection wires and connectors on the PFC. C and CN12: (yellow-yellow), connected to PFC inductance. R and CN12: (blue-red), CN12 CN12 ⑤ connected to rectifier. + and - : (red-blue), connected to P1 and P3 on PCB. CN7: (4p,red), connected to CN11 on PCB.
  • Page 125 7) Disconnect following connection wires and connectors between PCB and other components. P4: (blue), connected to N on IPM. P2: (red), connected to P on IPM. P1: (red), connected to + on PFC. P3: (blue), connected to – on PFC. RY4: (red), connected to rectifier.
  • Page 126 grounding wires of PCB. Remove the PCB board. ⑧ How to remove the compressor. ⑥ Compressor 1) Perform work of item 1,2,3 2) Remove electrical control box and partition plate. 3) Extract refrigerant gas. 4) Remove sound insulation material crankcase heating cable. 5) Remove terminal cover of compressor, and disconnect wires of compressor thermo...
  • Page 127 4-way How to remove the 4-way valve valve 1) Perform work of item 1,2. 2) Extract refrigerant gas. 3) Remove the electrical parts Coil from item 3. 4) Remove fixing screw of the Welded parts coil, and remove the coil. 5) Detach the welded parts of 4-way valve and pipe.

This manual is also suitable for:

M2od-18hfn1-mM3od-27hrdn1-mM3oc-30hrfn1-mM4oc-36hrfn1-m

Table of Contents