Midea M2OC-18HFN1-M, Service Manual

Page 1: ...fied 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 oth...

Page 2: ...or many years 11 6 6 Re installation while the indoor unit need to be repaired 11 6 7 Re installation while the outdoor unit need to be repaired 12 6 Electronic Function 13 7 1 Abbreviation 13 7 2 Ele...

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: ...Duct unit There should be only one Floor Ceiling Oasis or Duct unit 9 12 18 7 7 7 9 7 12 7 18 9 9 9 12 9 18 12 12 12 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 9 9 9 9 9 12 9 12 12 Mult...

Page 5: ...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 1...

Page 6: ...M MUBI 12HRDN1 M MUBU 12HRFN1 M 18K MSV1I 18HRDN1 M MS9AI 18HRDN1 M MCA2I 18HRDN1 M MCA2U 18HRFN1 M SUGGESTED INDOOR M3OC 30HRFN1 M 7K MS9AI 07HRDN1 M 9K MS9AI 09HRDN1 M A MSV1I 09HRDN1 M MS11M 09HRFN...

Page 7: ...in W D H W1 A B M2OC 18HFN1 M 845 33 3 320 12 6 700 27 6 908 35 7 560 22 335 13 2 M2OD 18HFN1 M 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...

Page 8: ...temp sensor T3 Condenser temp sensor T5 Discharge temp sensor T4 Ambient temp sensor INDOOR OUTDOOR EXV A CAPILIARY A CHECK VALVE CAPILIARY TUBE EXV B CAPILIARY B LIQUID VALVE B GAS VALVE B EXV C CAP...

Page 9: ...ngth for all rooms 73 8 0 161x lengt h for all rooms 98 4 Caution Refrigerant pipe diameter is different according to indoor unit to be connected When using the extension pipe refer to the tables belo...

Page 10: ...ressure Then remove the charge hose from the 3 way valve 8 Fully open the 2 way valve and 3 way valve and securely tighten the cap of the 3 way valve 2 Air purging by refrigerant Procedure 1 Confirm t...

Page 11: ...s leakage 6 5 Adding the refrigerant after running the system for many years Procedure 1 Connect the charge hose to the 3 way service port open the 2 way valve and the 3 way valve Connect the charge h...

Page 12: ...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 a...

Page 13: ...hose from the 3 way valve s service port immediately If the system has been charged with liquid refrigerant while operating the air conditioner turn off the air conditioner before disconnecting the ho...

Page 14: ...ICOOLLMT1 If the current frequency is lower than COOL_F4 the frequency will not be limited After 10s of the compressor start if the current ICOOL the AC will display the failure for 30 seconds and sto...

Page 15: ...g plugged in the crankcase heater will be active When T4 3 and the compressor is not running for 3 hours the crankcase heater will be active Preheating release condition When T4 5 or the indoor has ca...

Page 16: ...12 17 17 Modify rate 120 100 80 60 Note The final result is integer Then modify it according to T2 average correction Note Average value of T2 Sum T2 value of all indoor units indoor units number Acc...

Page 17: ...heating mode T3 TempQuitDefrost_ADD The defrosting time achieves 10min Turn to other modes or off 7 4 3 Outdoor fan control 7 4 3 1 Cooling mode For M3OD 27HRDN1 M 27 25 High Low When low ambient coo...

Page 18: ...ives the following modification commands If the T2B average the relevant valve needs more 16p open If the T2B average the relevant valve s open range remains If the T2B average the relevant valve need...

Page 19: ...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: ...ty 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 B...

Page 33: ...ion of compressor top P0 P3 Outdoor temperature is lower than 15 C optional function P4 Inverter compressor drive protection P5 Mode conflict Console series Operation Timer De frost Failure X X Open o...

Page 34: ...t 5Hz for ceiling floor flash 2 5Hz light X extinguished For MTBI 12HWDN1 M MTBI 18HWDN1 M Operation Timer De frost Alarm Failure Display ODU Error code X X X Open or short circuit of T1 temperature s...

Page 35: ...ver current protection P2 P3 X X Inverter compressor drive protection P4 X Mode conflict P5 flash at 2 5Hz light X extinguished flash at 0 5Hz Note Digital display is only available for duct type Oasi...

Page 36: ...compressor top only for M3OD 27HRDN1 M P0 5 times P4 Compressor drive error 6 times P5 Mode conflict flash light X extinguished 9 3 Outdoor Unit Display 9 3 1 Outdoor unit point check function There...

Page 37: ...nit is not connected the digital display tube will show 18 B indoor unit evaporator outlet temp T2BB 19 C indoor unit evaporator outlet temp T2BC 20 D indoor unit evaporator outlet temp T2BD 21 E indo...

Page 38: ...indoor units in good connection 44 Outdoor unit fan motor state Off 0 High speed 1 Med speed 2 Low speed 3 Breeze 4 Super breeze 5 45 The last error or protection code 00 means no malfunction and prot...

Page 39: ...for DC fan motor models F5 F1 No A Indoor unit coil outlet temp sensor or connector of sensor is defective F2 No B Indoor unit coil outlet temp sensor or connector of sensor is defective F3 No C Indoo...

Page 40: ...ting Supposed causes If the EEPROM chip is welded on PCB replace the PCB directly Otherwise check whether the EEPROM chip plugged in PCB well Yes No Yes Insert the EEPROM well Replace the indoor PCB S...

Page 41: ...en indoor and outdoor units diagnosis and solution Malfunction decision conditions Indoor unit does not receive the feedback from outdoor unit during 120 seconds Supposed causes Wiring mistake Indoor...

Page 42: ...remote controller Is all indoor unit display Turn off the all indoor units Is IPM power LED or operating LED lamp On Refer PIC2 Yes A Is all the wiring between terminal and Indoor PCB connect ok No Ye...

Page 43: ...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: ...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 27HRD...

Page 45: ...signal feedback for 4 minutes or the zero crossing signal time interval is abnormal Supposed causes Connection mistake PCB faulty Trouble shooting Check if the connections and power supply is normal C...

Page 46: ...playing the error code Shut off the power supply rotate the fan by hand Does it rotate properly The unit operates normally Find out the cause and have it solved For example check whether the fan is bl...

Page 47: ...r 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 If any resistance value is zero the fan...

Page 48: ...e voltage is less than 100V 208 240V power supply or 50V 115V power supply the PCB must have problems and need to be replaced 2 Indoor DC fan motor control chip is inside fan motor Power on and when t...

Page 49: ...t commercial except console NO Color Signal Voltage 1 Red Vs Vm 192V 380V 2 3 Black GND 0V 4 White Vcc 13 5 16 5V 5 Yellow Vsp 0 6 5V 6 Blue FG 15V For console NO Color Signal Voltage 1 Red VDC 310V 2...

Page 50: ...4 94V the LED will display the failure Supposed causes Wiring mistake Sensor faulty PCB faulty Trouble shooting Check the connections between temperature sensor and PCB Are the connections good Corre...

Page 51: ...function decision conditions When the voltage signal that IPM send to compressor drive chip is abnormal the display LED will show P6 and AC will turn off Supposed causes Wiring mistake IPM malfunction...

Page 52: ...work normally Check whether the lines in E part box are connected tightly Yes Connect it tightly check ok or not No No Yes No Replace the bridge rectifiers Check whether the bridge rectifiers are nor...

Page 53: ...about 187 253VAC Check the power supply Check whether the voltage of IPM board P and N is normal DC277 356V for 18 27KBtu h DC277 410V for 36KBtu h Replace bridge rectifiers and then check whether the...

Page 54: ...essor operates Whether refrigerant circulation volume is normal Whether abnormality is the same after gas charging Yes No No Reconnect and retest No Check refrigerant system such as clogging of capill...

Page 55: ...failure Supposed causes Wiring mistake Water level switch faulty Water pump faulty Indoor PCB faulty If the water level switch is inserted well No Insert the water level switch well If the water leve...

Page 56: ...or fan mode and indoor unit B is set to heating mode then A will change to off and B will work in heating mode Suppose Indoor unit A working in heating mode and indoor unit B is set to cooling mode or...

Page 57: ...mistake PCB faulty Trouble shooting If the EEPROM chip is welded on PCB replace the PCB directly Otherwise check whether the EEPROM chip plugged in PCB well Yes No Yes Insert the EEPROM well Replace t...

Page 58: ...ion Error Code E2 Malfunction decision conditions Indoor unit does not receive the feedback from outdoor unit during 120 seconds or outdoor unit does not receive the feedback from any one indoor unit...

Page 59: ...remote controller Is all indoor unit display Turn off the all indoor units Is IPM power LED or operating LED lamp On Refer PIC2 Yes A Is all the wiring between terminal and Indoor PCB connect ok No Ye...

Page 60: ...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 neg...

Page 61: ...PIC 4 Check point button press 1 time for check how many indoor units are connected Self Check Power Operating PIC3 Main board LED when power on and unit standby Pic 2 IPM For qua zone...

Page 62: ...Communication malfunction between IPM board and outdoor main board Is there at least one LED in the IPM board light Check the signal wire between the IPM module and the main board is it connected goo...

Page 63: ...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...

Page 64: ...ditions If the sampling voltage is lower than 0 06V or higher than 4 94V the LED will display the failure Supposed causes Wiring mistake Sensor faulty PCB faulty Trouble shooting Check the connections...

Page 65: ...ltage protection Check the voltage of outdoor unit power supply whether the voltage between L L1 and N L2 is about 187 253VAC Check the power supply Check whether the voltage of IPM board P and N is n...

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: ...module malfunction Trouble shooting PFC module protection Check whether the connecting line between main board and the PFC module is connected tightly Yes Check whether the voltage range of P N on IPM...

Page 71: ...Two ports of the inductance Inductance...

Page 72: ......

Page 73: ...on 1 minute later Is it still displaying the error code Shut off the power supply rotate the fan by hand Does it rotate properly The unit operates normally Find out the cause and have it solved For e...

Page 74: ...have problems and need to be replaced NO Color 1 Red 2 3 Black 4 White 5 Yellow 6 Blue Index2 1 DC fan motor control chip is inside fan motor Power on and when the unit is in standby measure the volt...

Page 75: ...t and output NO Color Signal Voltage 1 Red Vs Vm 140 380V M4OC 36HRFN1 M 263 400V M2OC 18HFN1 M M2OD 18HFN1 M 192 380V M3OC 30HRFN1 M 2 3 Black GND 0V 4 White Vcc 13 5 16 5V 5 Yellow Vsp 0 6 5V 6 Blue...

Page 76: ...block Outdoor PCB faulty Trouble shooting Temperature protection of compressor top Whether compressor operates Whether refrigerant circulation volume is normal Whether abnormality is the same after ga...

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Page 78: ...whether the system can run normally or test the resistance Yes No Connect it well Replace outdoor main board No Replace high pressure protector Yes Judge 2 Whether the high pressure protector is brok...

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Page 80: ...eplace low pressure protector Yes Judge 2 Whether the low pressure protector is broken Check whether the refrigerant system is ok Judge 3 Check whether the outdoor ambient temperature is too low No St...

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Page 82: ...erature is higher than 50 Judge 2 Check whether the outdoor ambient temperature is higher than 50 No Stop the unit Stop the unit Yes Judge 3 Check whether the outdoor unit is bad ventilation Judge 3 C...

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Page 84: ...g Temperature protection of compressor discharge Check whether the compressor discharge temp is more than 115 C Check whether the wiring connection is right between compressor discharge temp sensor an...

Page 85: ...tection of condenser Check whether the condenser temperature is more than 65 C Yes Judge 1 Check whether the outdoor ambient temperature is higher than 50 No Judge 3 The refrigerant pipe is blocked Le...

Page 86: ...nction decision conditions When the voltage signal that IPM send to compressor drive chip is abnormal the display LED will show P6 and AC will turn off Supposed causes Wiring mistake IPM malfunction O...

Page 87: ...the system can work normally Check whether the lines in E part box are connected tightly Yes Connect it tightly check ok or not No No Yes No Replace the bridge rectifiers Check whether the bridge rec...

Page 88: ...lease 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 Supposed causes EX...

Page 89: ...G YSK68 4B YSK27 4G YSK68 4B Model MCA2I 12HRDN1 M MCA2I 18HRDN1 M MCA2U 12HRFN1 M MCA2U 18HRFN1 M Indoor fan motor YDK45 6B YDK45 6B WZDK37 38G WZDK37 38G Model MUBI 12HRDN1 M MUBI 18HRDN1 M MUBU 12H...

Page 90: ...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 se...

Page 91: ...0 40060 3 41 5878 37 5 87359 77 1 29078 117 0 38991 2 39 8239 38 5 62961 78 1 25423 118 0 37956 1 37 1988 39 5 39689 79 1 21330 119 0 36954 0 35 2024 40 5 17519 80 1 17393 120 0 35982 1 33 3269 41 4 9...

Page 92: ...8 084 115 2 422 4 222 8 36 34 32 76 7 82 116 2 357 3 211 4 37 32 94 77 7 566 117 2 294 2 200 7 38 31 62 78 7 321 118 2 233 1 190 5 39 30 36 79 7 086 119 2 174 0 180 9 40 29 15 80 6 859 120 2 117 1 17...

Page 93: ...2 23 24 25 26 27 28 29 30 31 32 33 34 35 74 76 78 80 82 84 86 88 90 92 94 96 98 2 Compressor check Measure the resistance value of each winding by using the tester Position Resistance Value DA130S1C 2...

Page 94: ...resistance value Red Black Several M Red Black Several M P N U N U V V W W Red 4 AC Fan Motor Measure the resistance value of each winding by using the tester Position Resistance Value RPG20B RPG28H B...

Page 95: ...20 Yellow Blue 76 8 20 19 8 20 252 8 20 88 8 20 150 8 20 374 3 8 20 138 8 20 5 4 way valve 1 Power on use a digital tester to measure the voltage when the unit operates in cooling it is 0V When the un...

Page 96: ...6 EXV check Disconnect the connectors...

Page 97: ...Resistance to EXV coil Color of lead wire Normal Value Red Blue About 50 Red Yellow Brown Orange Brown White...

Page 98: ...Red Blue Red Yellow...

Page 99: ...Brown Orange Brown White...

Page 100: ...urn OFF the power breaker 2 Remove the screws of top cover and remove the top cover 9 screws 3 Remove the screws of right front side panel and remove the right front side panel 2 screws 4 Remove the s...

Page 101: ...fourteen screws of right rear panel and remove the right rear panel 2 Fan ass y How to remove the fan ass y 1 Remove the top cover right front side panel and front panel from item 1 step 1 4 2 Remove...

Page 102: ...stening four fixing screws 3 Electrical parts How to remove the electrical parts 1 Perform work of item 1 2 2 Remove the ten screws fixing the IPM board 3 Unfasten the connector of the reactor 4 Unfas...

Page 103: ...ors 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 3p 3p white whi...

Page 104: ...he electrical control box and partition plate 3 Extract refrigerant gas 4 Remove the sound insulation material and crankcase heating cable 5 Remove terminal cover of compressor and disconnect wires of...

Page 105: ...y valve How to remove the 4 way valve 1 Perform work of item 1 2 2 Extract refrigerant gas 3 Remove the electrical parts from item 3 4 Remove fixing screw of the coil and remove the coil 5 Detach the...

Page 106: ...ont side panel and remove the right front side panel 2 screws 4 Remove the screws of front panel and remove the front panel 9 screws 5 Remove the screws of big handle and remove the big handle 4 screw...

Page 107: ...over right front side panel and front panel from item 1 step 1 4 2 Remove the hex nut fixing the fan 3 Remove the fan 4 Remove the electrical control box cover Screws of big handle Screws of right rea...

Page 108: ...ews Note There are two kinds of screws Please pay attention to it when install the fan motor 3 Electrical parts How to remove the electrical parts 1 Perform work of item 1 2 2 Remove the ten screws fi...

Page 109: ...r parts Connectors CN17 T3 T4 temp sensor 2p 2p white CN7 Tdischarge temp sensor 2p white CN12 Ttop temp sensor 2p white CN15 T2B A B C temp sensor 2p 2p 2p white CN18 CN19 CN22 Electronic expansive v...

Page 110: ...item 1 2 3 2 Remove the electrical control box and partition plate 3 Extract refrigerant gas 4 Remove the sound insulation material and crankcase heating cable 5 Remove terminal cover of compressor a...

Page 111: ...nductance 4 Disconnect two pieces of wires connected from the cover of inductance 5 Remove two screws of reactor and remove the reactor 6 The 4 way valve How to remove the 4 way valve 1 Perform work o...

Page 112: ...sion valve How to remove the expansion valve 1 Perform work of item 1 2 2 Remove the electrical parts from item 3 3 Remove the coils 4 Detach the welded parts of expansion valves and pipes Coils Expan...

Page 113: ...he screws of right front side panel and remove the right front side panel 2 screws 4 Remove the screws of front panel and remove the front panel 10 screws 5 Remove the screws of big handle and remove...

Page 114: ...Screws of front panel Screws of right rear panel Screws of top cover...

Page 115: ...electrical control box cover 5 Disconnect the fan motor connector CN37 5p white from the PCB board 6 Remove the fan motor after unfastening six fixing screws 3 Electrical parts How to remove the elect...

Page 116: ...5 Disconnect following 5 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: ...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 Wires CN1 CN2 4 way valve blue blue CN5 CN6 Crankcase heating cable red red...

Page 118: ...erant gas 4 Remove the sound insulation material and crankcase heating cable 5 Remove terminal cover of compressor and disconnect wires of compressor thermo and compressor from the terminal 6 Remove t...

Page 119: ...of wires connected from the cover of inductance 5 Remove two screws of reactor and remove the reactor 6 The 4 way valve How to remove the 4 way valve 1 Perform work of item 1 2 2 Extract refrigerant g...

Page 120: ...sion valve How to remove the expansion valve 1 Perform work of item 1 2 2 Remove the electrical parts from item 3 3 Remove the coils 4 Detach the welded parts of expansion valves and pipes Coils Expan...

Page 121: ...nt side panel and remove the right front side panel 2 screws 4 Remove the screws of front panel and remove the front panel 10 screws 5 Remove the screws of big handle and remove the big handle 4 screw...

Page 122: ...Screws of big handle Screws of right rear panel Screws of water collector Screws of terminal board...

Page 123: ...unfastening four fixing screws 3 Electrical parts How to remove the electrical parts 1 Perform work of item 1 2 2 Disconnect the following connection wires and connectors on the IPM P red connected to...

Page 124: ...N12 blue red connected to rectifier and red blue connected to P1 and P3 on PCB CN7 4p red connected to CN11 on PCB CN8 2p white connected to CN202 on IPM 5 Remove the PFC board after remove the two sc...

Page 125: ...se heating cable CN11 4p red connected to CN7 on PFC CN13 T2B A B C D temp sensor 2p 2p 2p 2p white CN33 Tdischarge temp sensor 2p white CN8 T3 T4 T3 T4 temp sensor 2p 2p white CN9 High and low pressu...

Page 126: ...te 3 Extract refrigerant gas 4 Remove the sound insulation material and crankcase heating cable 5 Remove terminal cover of compressor and disconnect wires of compressor thermo and compressor from the...

Page 127: ...Remove fixing screw of the coil and remove the coil 5 Detach the welded parts of 4 way valve and pipe 6 The expansion valve How to remove the expansion valve 1 Perform work of item 1 2 2 Remove the e...

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