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SERVICE MANUAL MUFZ-KJ25VE - A1 MUFZ-KJ35VE

1. 5 BRN 4 3 MC E BLU X65 z PTC64 RED a E aa 5 GRN YLW e F oTABS3 MS c 2 INVERTER TB2 WHI b C BOARD a RELAY P C BOARD LED 481 B L cB C932 8 z NE 7801 F880 F90 sg i E EL X69 eye it TAB71 eu eut 3 BLK E S O z CN70 z x DEL CN67 CN672 CN673 _ CN724 C c z BLK 3 gt 9000 o o 7 LDE 2 2 6 2 l 6 29 5 2154 Hd 4A d t l Lt ES E RT61 RT62 RT68 RT65 RT64 LEV SYMBOL NAME SYMBOL NAME SYMBOL NAME SYMBOL NAME 3 SMOOTHING CAPACITOR L REACTOR R162 DISCHARGE TEMP THERMISTOR X602 RELAY CN70 CONNECTOR LED LED RT64 FIN TEMP THERMISTOR X64 RELAY F601 FUSE T3 15AL250V LEV _ EXPANSION VALVE COIL 5 TEMP THERMISTOR X65 RELAY F880 FUSE T3 15AL250V MC COMPRESSOR UTDOOR HEAT EXCHANGER X69 RELAY F901 FUSE T3 15AL250V MF FAN MOTOR TEMP THERMISTOR 2154 REVERSING
2. FUNCTION SPL dB A LINE FUNCTION SPL dB A LINE COOLING 46 ee COOLING 47 oe HEATING 51 0 HEATING 51 0 90 TI I I 4 90 5 sj R amp g g 70 8 70 d z z iy 60 60 a c z 2 50 50 ul ul t c a a Z 40 Z 40 7 7 a a 2 30 2 30 4 4 m m NC 30 w w TI j gt gt 20 i 20 ES F E 3 T NC 20 I vei NC 20 I I NC 10 i i T t x 10 da L 10 ae i 63 125 250 500 1000 2000 4000 8000 63 125 250 500 1000 2000 4000 8000 BAND CENTER FREQUENCIES Hz BAND CENTER FREQUENCIES Hz Test conditions Cooling Dry bulb temperature 35 C Heating Dry bulb temperature 7 C Wet bulb temperature 6 C OUTDOOR UNIT MUFZ KJ50VE 1m MICROPHONE FUNCTION SPL dB A LINE COOLING 49 e 9 HEATING 52 0 90 I 7 T 7 c I 1 3 3 3 T 80 1 N i i i T Ep B 3 70 ae T i i i NC 70 g i R PM CA ems 60 r F r I NC 60 5 5 an o PP J 50 c NC 50 2 5 40 o ANN o r lt 30 MS a T ui i I gt i 3 NC 20 i NC 10 i i 10 63 125 250 500 1000 2000 4000 8000 BAND CENTER FREQUENCIES
3. 724 1084 12 2 1 3 M 6 6 9 84 1104 5 12 5 22 EG E 26 24 20 2g 6 0 8 8 9 9 5 1 1 18 54 7 9 89 9 10 o o0 E 9 4 8 7 0 7 8 5 0 9 8 4 2 6 1 6 81 0 8 Indoor intake air Wet bulb LLLLELLLLLLLLILILILI 10 5 0 5 10 15 20 25 30 35 40 45 2 2 3 2 Outdoor intake air Dry bulb temperature C x x x N N N Lu Lu Lu 2 E z z z Heating capacity at Rated frequency difference C Indoor air Dry bulb temperature 10 15 Outdoor intake air Wet bulb temperature C MUFZ KJ25VE MUFZ KJ35VE MUFZ KJ50VE Total input Heating at Rated frequency 22 9 29 0 274 13 21 2 26 8 25 0 E 12 26 9 1944 2454 2294 8 5 S 131 mee 15 amp 17 6 223 208 710 von Pie iz 5 intake PLN Ez or 15 9 20 1 18 8 50 9 woo 2 2g 14 1 4 17 8 4 16 7 0 8 s 12 3 4 15 6 4 146 997 o 5 106 1344 1254 206 5 8 8 11 144 104 0 5 E 7 1 8 9 8 3 0 4 15 10 5 0 5 10 15 io o Outdoor intake air Wet bulb temperature C lar 9 x y y N N N LL L LL 2 2 2 NOTE
4. Y Was the indoor unit ever connected to the Multi Yes N MXZ series and operated turned on No The connection information to the Multi series is stored in the indoor unit Refer to Deleting the memorized abnormal condition described in 11 2 1 to clear the error history When the error history is being cleared the connection information also will be initialized The indoor unit will be compatible with a low standby power model after initialization Turn OFF inverter controlled lighting equipment Turn OFF the power supply and then turn ON again Press EMERGENCY OPERATION switch Y A ane Reinstall either the unit or the light Is serial signal away from each other error indicated Attach a filter on remote control S ETT receiving section of the indoor unit urn the power supply ON Y N Check for miswiring broken wires and loose wire Is there rated voltage between outdoor terminal block S1 and S2 connection between the power supply and outdoor terminal block S1 and between the power supply and Yes outdoor terminal block S2 Wait for 2 or more minutes after the power supply is turned on Touch S2 and 53 with tester probes and start the emergency operation When the emergency operation starts does the rated voltage occur for 2 sec No onds between indoor terminal block S2 and S3 Yes Does the left lamp of the OPERA
5. e Model MUFZ KJ25VE MUFZ KJ35VE Smoothing capacitor C61 C62 600 yF 620 uF 420 V Diode module DB61 15A600 V F61 T20AL250V Fuse F701 F801 F901 T3 15AL250V 1 700 15 A600 V Power module 1C932 8A600V c d valve LEV 12 V DC Reactor L61 23 mH Power factor controller 8820 20A 600V Circuit protection PTC64 PTC65 330 Terminal block TB 5P X63 3A250 V Relay X64 20 A 250 V X69 10A 250V R V coil 2154 220 240 VAC Specifications and rated conditions of main electric parts MUFZ KJ50VE CB1 CB2 CB3 560 uF 450 V F601 F880 F901 T3 15AL250 V IGBT module 1 932 5 A 600 V IC700 20 A 600 V Expansion valve coil LEV 12 VDC L 340 uH IC820 20A600 V protection 330 Terminal block TB1 TB2 3P Relay X64 20A 250V X65 20A 250V X69 10A 250V X601 3A250V X602 3A250V PTC64 PTC65 2184 OBH695 220 240 V AC 4 NOISE CRITERIA CURVES
6. H am CNT WHT Omama CIRCUIT TB BREAKER N 230V 50Hz 3 3 CNEL N643 CN641 CN644 CNI24 ool ool 1 00 of t o o o o o Off NOTES 1 pe z di 1 About the indoor side electric 165 are 2 Mir wiring refer to the indoor unit electric wiring diagram for servicing LEV F6l Use copper conductors only For field wiring Symbols indicate TI Terminal block SYMBOL NAME SYMBOL NAME SYMBOL NAME CN70 CONNECTOR LED LED RT64 FIN TEMP THERMISTOR C61 C62 SMOOTHING CAPACITOR LEV EXPANSION VALVE COIL RT65 AMBIENT TEMP THERMISTOR DB61 DIODE MODULE 161 REACTOR RT68 OUTDOOR HEAT EXCHANGER F61 FUSE T20AL250V MC COMPRESSOR TEMP THERMISTOR F701 F801 F901 FUSE T3 15AL250V MF FAN MOTOR TB TERMINAL BLOCK 1C700 1 820 POWER MODULE PTC64 PTC65 CIRCUIT PROTECTION T801 TRANSFORMER 16932 RT61 DEFROST THERMISTOR X63 X64 X69 RELAY 1C802 POWER DEVICE RT62 DISCHARGE TEMP THERMISTOR 2154 REVERSING VALVE COIL OBH695 TO INDOOR UNIT MUFZ KJ50VE CIRCUIT BREAKER 181
7. Resistance kQ Resistance kQ Resistance k 0 0 0 20 10 0 10 20 30 40 0 30 20 30 T 50 60 aS 80 80 100 110 120 0 10 20 30 40 5 TES 70 8 80 Temperature C Temperature C OBH695 2 Relay P C board MUFZ KJ50VE To inverter P C board CN681 CN680 L68A OBH695 t 12 DISASSEMBLY INSTRUCTIONS lt Terminal with locking mechanism Detaching points gt The terminal which has the locking mechanism can be detached as shown below There are two types refer to 1 and 2 of the terminal with locking mechanism The terminal without locking mechanism can be detached by pulling it out Check the shape of the terminal before detaching 1 Slide the sleeve and check if there is a locking lever or not 2 The terminal with this connector has the locking mechanism Sleeve Slide the sleeve the sleeve and Pull the terminal while pull out the terminal Locking lever pushing the locking slowly lever Connector 12 1 MUFZ KJ25VE MUFZ KJ35VE NOTE Turn OFF power supply before disassembly OPERATING PROCEDURE PHOTOS 1 Removing the cabinet Photo 1 1 Remove the screw fixing the service panel Screws of the 2 Pull down the service panel and remove it top panel Screws of 3 Disconnect the power supply and indoor outdoor con 1 the top panel necting wire 4 Remove the screws fixing the top panel 5 Remove the top pan
8. PERFORMANCE DATA COOL operation at Rated frequency MUFZ KJ25VE CAPACITY 2 5 kW SHF 0 847 SHC 35 SHF INPUT INPUT 540 W OUTDOOR DB C 40 SHC SHF INPUT Q 46 SHC SHF INPUT NOTE Q Total capacity kW SHC Sensible heat capacity kW OBH695 SHF Sensible heat factor INPUT Total power input W 17 DB Dry bulb temperature WB Wet bulb temperature PERFORMANCE DATA COOL operation at Rated frequency MUFZ KJ35VE CAPACITY 3 5 kW SHF 0 73 INPUT 900 W OUTDOOR DB C 25 27 30 SHF INPUT Q SHC SHC SHF INPUT 2 08 2 00 0 55 828 1 72 1 66 0 43 855 NOTE Q Total capacity kW SHF Sensible heat factor DB Dry bulb temperature SHC Sensible heat capacity kW INPUT Total power input W WB Wet bulb temperature OBH695 i PERFORMANCE DATA COOL operation at Rated frequency MUFZ KJ35VE CAPACITY 3 5 kW SHF 0 73 INPUT 900 W OUTDOOR DB C 40 SHC SHF INPUT NOTE Q Total capacity kW SHF Sensible heat factor DB Dry bulb temperature SHC Sensible heat capacity kW INPUT Total power input W WB Wet bulb temperature OBH695 D PERFORMANCE DATA COOL operation at Rated frequency MUFZ KJ50VE CAPACITY 5 0 kW SHF 0 71 INPUT 1400 W OUTDOOR DB C 25 27 30
9. Coefficient of performance Cooling 4 63 3 57 COP 1 Set Heating 4 42 3 87 Model SNB140FRUMT SNB172FEKMT Output 950 1 200 Compressor Cooling Heating Current 1 5 18 5 54 Refrigeration oil Model 0 35 FV50S 0 40 FV50S Model RC0J50 CI RC0J60 BC Fan motor Cooling t 1 Current Heating 0 28 0 82 0 31 0 82 Dimensions W x H x D 800 x 550 x 285 840 x 880 x 330 Weight 37 55 Dehumidification Cooling 2 0 Med Low High Med Low Cooling Air flow 2 1 Heating 2 748 1 632 2 856 2 748 2 274 Cooling Heating Sound level SPL 1 49 52 Med Low High Med Low Cooling Special remarks Fan speed Heating Fan speed regulator Refrigerant filling capacity R410A NOTE Test conditions are based on AS NZS3823 1 1 Refrigerant piping length one way 7 5 m 1 Measured under rated operating frequency COOLING INDOOR Dry bulb temperature OUTDOOR Dry bulb temperature HEATING INDOOR Dry bulb temperature OUTDOOR Dry bulb temperature OBH695 27 0 C 35 0 C 20 0 C 7 0 C Wet bulb temperature 19 0 C Wet bulb temperature 24 0 C Wet bulb temperature 6 0 C Specifications and rated conditions of main electric parts
10. NOTE Measure the voltage by an analog tester Replace the LEV coil Yes Replace the expansion valve NOTE After check of LEV do the undermentioned operations 1 Turn OFF the power supply and turn it ON again 2 Press RESET button on the remote controller OBH695 Check of inverter P C board Check the outdoor fan motor Refer to 11 5 00 Y Is the fuse F901 blown on the in verter P C board Yes No Y Check the connection of the connectors CN931 CN932 of the outdoor fan motor If the connection is poor make it correct Operate the outdoor unit by starting EMERGENCY OPERATION Check the LED indication on the in Check the corresponding parts verter P C board N following LED indication Does the LED flash 10 times 9 Refer to 11 3 Yes 10 time flash Replace the inverter P C board E OBH695 ii How to check miswiring and serial signal error MUFZ KJ25 35 Turn OFF the power supply Is there rated voltage in the power supply Y Yes Turn ON the power supply Y No Check the power supply there rated voltage between outdoor terminal block S1 and S2 Y Yes Y Does the left lamp of OPERATION INDICATOR lamp on the indoor unit of the power supply to the indoor unit ight up
11. Changes for the Better MITSUBISHI ELECTRIC SPLIT TYPE AIR CONDITIONERS OUTDOOR UNIT SERVICE MANUAL M No OBH695 R410A Models MUFZ KJ25VE MUFZ KJ35VE MUFZ KJ50VE Indoor unit service manual MFZ KJ VE Series OBH697 CONTENTS 4 TECHNICAL CHANGES ssssausauaussuassuaussuanuuans 3 2 PART NAMES AND FUNCTIONS 3 SPECIFICATION 4 4 NOISE CRITERIA CURVES TT TIT 6 5 OUTLINES AND DIMENSIONS 7 6 WIRING DIAGRAM 8 7 REFRIGERANT SYSTEM DIAGRAM 10 8 PERFORMANCE CURVES 12 9 ACTUATOR CONTROL TT 23 10 SERVICE FUNCTIONS 24 gt 11 TROUBLESHOOTING 25 MUFZ KJ25VE 12 DISASSEMBLY INSTRUCTIONS 48 MUFZ KJ35VE PARTS CATALOG OBB695 NOTE RoHS compliant products have lt G gt mark on the spec name plate Use the specified refrigerant only Never use any refrigerant other than that specified Doing so may cause a burst an explosion or fire when the unit is being used serviced or disposed of Correct refrigerant is specified in the manuals and on the spec labels provided with our produc
12. The unit of pressure has been changed to MPa on the international system of units SI unit system The conversion factor is 1 MPa Gauge 10 2 kgf cm Gauge Outdoor unit current MUFZ KJ25VE MUFZ KJ35VE MUFZ KJ50VE 3 0 4 5 8 lt 40 lt g25 t 3 g g 3 53 5 8 o o o 8 lt 220 8 8 53 0 8 1 5 25 15 20 25 30 35 15 20 25 30 35 50 60 70 50 60 70 Ambient temperature C Ambient temperature C Ambient temperature C Ambient humidity Ambient humidity Ambient humidity HEAT operation Condition Indoor Outdoor Dry bulb temperature C 20 0 7 15 Wet bulb temperature C 14 5 6 12 Operation Test run operation Refer to 8 3 Outdoor unit current MUFZ KJ25VE MUFZ KJ35VE MUFZ KJ50VE 4 5 6 0 9 Z4 0 z 8 5 P 7 83 5 E 3 5 6 3 0 O 5 2 5 f 4 0 5 10 15 20 25 0 5 10 15 20 25 0 5 10 15 20 25 Ambient temperature C Ambient temperature C Ambient temperature C OBH695 n PERFORMANCE DATA COOL operation at Rated frequency MUFZ KJ25VE CAPACITY 2 5 kW SHF 0 847 INPUT 540 W OUTDOOR DB C 25 27 30 SHF INPUT Q SHC SHC SHF INPUT 1 80 1 73 0 67 497 1 56 1 50 0 55 513 NOTE Q Total capacity kW SHF Sensible heat factor DB Dry bulb temperature SHC Sensible heat capacity kW INPUT Total power input W WB Wet bulb temperature OBH695 E
13. power model or a non low standby power model will also be initialized Default compatible with a low standby power model the remote controller headed towards the indoor unit 8 Press EMERGENCY OPERATION switch so that the memorized abnormal condition is deleted x3 2 Release the failure mode recall function according to Releasing the failure mode recall function men tioned above NOTE 1 Make sure to release the failure mode recall function after it is set up otherwise the unit cannot operate properly 2 If the abnormal condition is not deleted from the memory the last abnormal condition is kept memorized 2 pattern when outdoor unit is abnormal i i Blinking at 0 5 Blinking at 0 5 2 5 second OFF 3 second ON second interval 2 5 second OFF 3 second ON second interval lt gt lt gt lt gt lt p gt 4 gt lt gt NS oo fy rh OFF gt gt gt gt gt gt gt _ gt BSS ge NO CDC Sg i i No beep 1 Beeps i No bee i Beeps i Repeated cycle i Repeated cycle Repeated cycle OBH695 3 Outdoor unit failure mode table Left lamp of the OPERATION INDICATOR lamp Indoor unit Abnormal point Failure mode protection LED indication Outdoor P C board Condition Indoor outdoor unit failure mode recall function Outdoor unit failure mode recall function OFF None Normal 1 time fl
14. 5 Remove the fan motor Removing the compressor and 4 way valve 1 Remove the top panel cabinet and service panel Refer to 1 2 Remove the back panel Refer to 1 3 Remove the inverter assembly Refer to 2 4 Recover gas from the refrigerant circuit NOTE Recover gas from the pipes until the pressure gauge shows 0 MPa 5 Detach the brazed part of the suction and the discharge pipe connected with compressor 6 Remove the compressor nuts 7 Remove the compressor 8 Detach the brazed parts of 4 way valve and pipe Photo 4 OBH695 Photo 5 Outdoor heat exchanger temperature thermistor Ambient temperature thermistor Photo 6 Screws of the outdoor fan motor Photo 7 Brazed part of the discharge pipe Discharge temperature thermistor Brazed part of the suction pipe MITSUBISHI ELECTRIC CORPORATION HEAD OFFICE TOKYO BLDG 2 7 3 MARUNOUCHI CHIYODA KU TOKYO 100 8310 JAPAN Copyright 2014 MITSUBISHI ELECTRIC CORPORATION Distributed in Apr 2014 No OBH695 New publication effective Apr 2014 Made in Japan Specifications are subject to change without notice
15. Refer to 11 6 1 2 LED is lighted during normal operation Inverter F C board MUFZ KJ25 35VE The flashing frequency shows the number of times the LED blinks after every 2 5 second OFF Example When the flashing frequency is 2 Flashing gt 0 5 0 5 A A 2 ON 2 5 second OFF MUFZ KJ50VE Flashing LED OBH695 11 4 TROUBLE CRITERION OF MAIN PARTS MUFZ KJ25VE MUFZ KJ35VE MUFZ KJ50VE Part name Check method and criterion Figure Defrost thermistor RT61 Fin temperature thermistor RT64 Ambient temperature thermistor RT65 Outdoor heat exchanger temperature thermistor RT68 Measure the resistance with a tester Refer to 11 6 Test point diagram and voltage 1 Inverter P C board for the chart of thermistor Discharge temperature Measure the resistance with a tester Before measurement hold the thermistor with your hands to warm it up thermistor RT62 Refer to 11 6 Test point diagram and voltage 1 Inverter P C board for the chart of thermistor Measure the resistance between terminals using a tester Temperature 10 40 C WHT RED BLK Normal Q Compressor MUFZ KJ25 35VE MUFZ KJ50VE 1 66 2 26 0 87 1 18 Outdoor fan motor Measure the resistance between lead wires using a tester Temperature 10 40 C Normal Q Color o
16. The above broken lines are for the heating operation without any frost and defrost operation OBH695 8 2 CAPACITY AND INPUT CORRECTION BY OPERATIONAL FREQUENCY OF COMPRESSOR MUFZ KJ25VE m Correction of Cooling capacity Correction of Cooling input 30 Correction of Heating capacity 3 Correction of Heating input D ot o 2 p 5 2 Sis 8 c o c 5 510 S 2 5 82 8 5 8 9 1 0 8 3 8 20 5 5 2 21 90 5 Q gt amp S o O 0 50 100 100 0 50 100 150 0 50 100 150 The operational frequency The or frequency The operational frequency The operational frequency of compressor Hz of compressor Hz of compressor Hz of compressor Hz MUFZ KJ35VE Correction of Cooling capacity LM of Cooling input Correction of Heating capacity Correction of Heating input 1 5 22 3 o o 8 s 8 915 g 5 1 0 81 0 8 8 2 8 5 8 1 0 S 8 8 0 5 50 5 g E 1 8 T 0 5 8 8 3 5 0 50 100 0 50 100 150 0 50 100 150 The operational frequency The The operational frequency The operational frequency of compressor Hz of compressor Hz of compressor Hz of compressor Hz MUFZ KJ50VE Correction of Cooling capacity 3 Correction of Cooling input b o Correction of Heating capacity 25 Correction of Heating input E B15 81 815 820 c E 5 5 5 5 1 5 91 0 1 1 91 0 8 8 8 1 0 2 8 gt 90 5 50 5 50 5 05 a Q g V oO c k O 0 50 100 0 5
17. does not op erate 1 time flash every 2 5 seconds Outdoor power sys tem Overcurrent protection cut out operates 3 consecutive times within 1 minute after the compressor gets started Reconnect the connector of the compressor Refer to 11 5 How to check in verter compressor Check the stop valve Outdoor thermistors Discharge temperature thermistor fin temperature thermistor defrost thermistor P C board temperature thermistor outdoor heat exchanger temperature thermistor or ambient tempera ture thermistor shorts or opens during compressor running Refer to 11 5 Check of outdoor thermistors Outdoor control sys tem Nonvolatile memory data cannot be read properly POWER lamp of the indoor unit lights up or flashes 7 time Replace the inverter P C board 6 time flash 2 5 seconds OFF Serial signal The communication fails between the indoor and outdoor unit for 3 minutes eCheck connection between the in verter P C board and the relay P C board KJ50 Refer to 11 5 How to check miswiring and serial signal error 11 time flash 2 5 seconds OFF Stop valve Closed valve Closed valve is detected by compressor current Check the stop valve 14 time flash 2 5 seconds OFF Outdoor unit Other abnormality Outdoor unit is defective Refer to 11 2 2 Flow chart of the detailed outdoor unit failure mode recall function 16 time flash 2 5
18. Confirmation Y Yes Check the wiring No Press EMERGENCY OPERATION switch once Y s the serial signal error indicated 6 minutes later No Is there any miswiring poor contact or wire dis connection of the indoor outdoor connecting wire Yes lt Yes y Was the indoor unit ever connected to Yes turned on the Multi MXZ series and operated The connection information to the Multi series is stored in the indoor unit Refer to Deleting the memorized abnormal condition described in 11 2 1 to clear the error history When the error history is being cleared the connection information also will be initialized The indoor unit will be compatible with a low standby power model after initialization Y A Y B the power su pply ON Y Is there rated voltage between outdoor terminal block S1 and S2 Yes Y Correct the wiring A Turn OFF inverter controlled lighting equipment Turn OFF the power supply and then turn it ON again Press EMERGENCY OPERATION switch Reinstall either the unit or the light away from each other Attach a filter on remote control receiving section of the indoor unit Is serial signal error indicated 6 minutes later Wait for 2 or more minutes after the power supply is turned on Touch S2 and S3 with test
19. Hz OBH695 i 5 OUTLINES AND DIMENSIONS Unit mm MUFZ KJ25VE REQUIRED SPACE M U FZ KJ35VE 1 100 mm or more when front and sides of the unit are clear 304 325 Bolt pitch for installation 2 When any 2 sides of left right and rear of the unit are clear Service panel Liquid refrigerant pipe joint Gas refrigerant pipe joint Refrigerant pipe flared 29 52 500 Bolt pitch for installation 500 Bot pich ton 1 MUFZ KJ50VE REQUIRED SPACE 1 500 mm or more when front and sides of the unit are clear 417 5 Drain hole 42 Air in 40 1 8 1 1 8 1 Air out 2 holes 10X 21 175 500 J 2 When any 2 sides of left right and rear of the unit are clear Service panel Liquid refrigerant pipe joint Refrigerant pipe flared 6 35 880 Gas refrigerant pipe joint Refrigerant pipe flared 12 7 164 5 99 5 a 195 OBH695 f 6 WIRING DIAGRAM MUFZ KJ25VE MUFZ KJ35VE no 3 1 U E ED MC W 2154 1801 801 kd m P INVERTER P C BOARD LED
20. Open windows and doors of room 5 Press the EMERGENCY OPERATION switch once twice to start the EMERGENCY COOL HEAT MODE 6 When system stabilizes after more than 15 minutes measure temperature and take an average temperature 7 10 minutes later measure temperature again and check that the temperature does not change INDOOR UNIT OUTDOOR UNIT I Wet and dry bulb thermometers We Wet and dry bulb Wet and dry bulb thermometers thermometers FRONT VIEW BACK VIEW 8 1 CAPACITY AND INPUT CURVES Cooling capacity at Rated frequency g 8 5 12 9 14 6 1 5 TT IM n T ri ndoor intake air Wet bulb 5 7 9 11 8 13 4 8 1 4 temperature C 1 7 2 10 84 122 43 2 9 66 9 8 11 0 42 ew i o o o o 2g 6 0 8 8 9 9 gt 1 1 24 o S 5 4 7 9 8 9 g 1 0 5 o _ o 22 E 4 8 7 0 7 8 0 9 20 18 w w w 10 5 0 5 10 15 20 25 30 35 40 45 5 2 N Outdoor intake air Dry bulb temperature C x D D D gt gt 12 O UJ IL Total input Cooling at Rated frequency
21. TION INDICATOR lamp onthe Does DC 10 V or more occur Replace the outdoor inverter indoor unit blink continuously between L68A and L68B on the board and the outdoor relay P C control P C board 6 minutes after the emergency outdoor relay P C board operation starts board 1 Yes Yes board 1 Y Does the outdoor LED blink 6 No OD IE 3 times board 1 Yes y Does DC more than 0 V occur 7 ieee indoor terminal block S2 No nopage ne e veneers and 53 Yes Y Turn the power supply OFF X1 Electric charge may remain immediately Y after the power supply is turned OFF Replace the indoor electronic Perform the procedure after 3 minutes control P C board Y Turn the power supply ON Y Start the emergency operation Y Does the left lamp of the OPERA TION INDICATOR lamp on the indoor unit blink continuously Repair has been completed 6 minutes after the emergency operation starts yes Replace the outdoor inverter board and the outdoor relay P C OBH695 N Check of outdoor refrigerant circuit Was the eceration sated with The unit occasionally stops when the Has the operation stopped the sto closed and was stop valve is opened or closed during during pump down No it pa during operation Yes Open the stop valve and start the coo
22. VALVE COIL 10700 1GBT MODULE PTC64 CIRCUIT PROTECTION TB2 TERMINAL BLOCK 1C820 DIODE MODULE PTC65 CIRCUIT PROTECTION 1801 TRANSFORMER 10932 1GBT MODULE RT61 DEFROST THERMISTOR X601 RELAY NOTES 1 About the indoor side electric wiring refer to the indoor unit electric wiring diagram for servicing 2 Use copper conductors only for field wiring 3 Symbols indicate Terminal block OBH695 i 7 REFRIGERANT SYSTEM DIAGRAM MUFZ KJ25VE Unit mm MUFZ KJ35VE Refrigerant pipe 09 52 with heat insulator 4 way valve S x Outdoor heat exchanger 7 Stop x 1 temperature Muffler utdoor ermistor Flared connection fl heat T68 temperature exchanger ll thermistor RT62 Compressor Ambient femperature i gen Defrost 33383 Perel Capillary tube R 3 0x 2 0x210 I Strainer 100 Flared connection Capillary tube LEV 4 0x 2 4x240 gt lt R V coil heating ON 000 gt cooling OFF Stop valve with strainar Refrigerant pipe 26 35 gt Refrigerant flow in cooling with heat insulator gt Refrigerant flow in heating MUFZ KJ50VE i Muffler Refrigerant pipe 212 7 with heat insulator 4 way valve 100 Discharge t Ambient temperature Defrost thermistor thermistor RT65 RT61 Compressor Outdoor heat exchanger temperature thermistor RT
23. board gt CN931 CN932 Fan motor 3 Remove the propeller nut 4 Remove the propeller 5 Remove the screws fixing the fan motor 6 Remove the fan motor 6 Removing the compressor and 4 way valve 1 Remove the cabinet and panels Refer to 1 2 Remove the inverter assembly Refer to 2 3 Recover gas from the refrigerant circuit NOTE Recover gas from the pipes until the pressure gauge shows 0 MPa 4 Detach the brazed part of the suction and the discharge pipe connected with compressor 5 Remove the nuts of compressor legs 6 Remove the compressor 7 Detach the brazed part of pipes connected with 4 way valve Photo 9 Suction pipe Discharge pipe brazed part brazed part Brazed parts of 4 way valve OBH695 i Photo 6 Photo 7 Photo 8 Propeller Outdoor heat exchanger tempera ture thermistor Defrost thermistor ee F Ambient temperature Screws of the outdoor fan motor Ps Propeller nut 12 2 MUFZ KJ50VE NOTE Turn OFF power supply before disassembly OPERATING PROCEDURE PHOTOS Photo 1 1 Removing the cabinet Screws of the top panel 1 Remove the screws of the service panel 2 Remove the screws of the top panel 3 Remove the screw of the valve cover 4 Remove the service panel 5 Remove the top panel 6 Remove the valve cover 7 Disconnect the power supply and indoor outdoor connect ing wire 8 Remove the s
24. capacity kW INPUT Total power input W DB Dry bulb temperature WB Wet bulb temperature OBH695 9 ACTUATOR CONTROL MUFZ KJ25VE MUFZ KJ35VE MUFZ KJ50VE 9 1 OUTDOOR FAN MOTOR CONTROL The fan motor turns ON OFF interlocking with the compressor ON The fan motor turns ON 5 seconds before the compressor starts up OFF The fan motor turns OFF 15 seconds after the compressor has stopped running 5 seconds 15 seconds OFF ON lt gt lt lt Compressor OFF ON Outdoor fan motor OFF 9 2 R V COIL CONTROL Heating Cooling ta P erties ete M OFF Diy m OFF NOTE The 4 way valve reverses for 5 seconds right before start up of the compressor COOL HEAT 5 seconds 5 seconds ON EE Compressor Heo ON F1 Outdoor fan ON i motor OFF 9 3 RELATION BETWEEN MAIN SENSOR AND ACTUATOR Actuator Sensor Purpose p Compressor Indoor fan Defrost R V coil motor heater Discharge temperature Protection thermistor O Cooling Coil frost prevention Indoor coil temperature thermistor Heating High pressure protec tion Defrost thermistor Heating Defrosting Fin temperature thermistor Protection Cooling Low ambient tempera Ambient temperature ture operation thermistor Heating Defrosting Heater Cooling Low ambient tempera Outdoor heat exchanger tem ture opera
25. received NOTE It takes up to 1 minute to indicate the outdoor unit abnormality Even if the OPERATION INDICATOR lamp is not lighting keep checking at least 1 minute or longer Does the left lamp of the OPERATION INDICATOR lamp on the indoor unit blink at the interval of 0 5 seconds Blinks The outdoor unit is abnormal Beep is emitted at No the same timing as the blinking of the left lamp OFF of the OPERATION INDICATOR lamp 2 Yes jain The outdoor unit is abnormal Check the blinking pattern and identify the abnormal point by referring to the outdoor unit failure mode table 11 2 3 Make sure to check at least two consecutive blinking cycles 2 The outdoor unit is normal Releasing the failure mode recall function Release the failure mode recall function by the following procedures Release the failure mode recall function accord Turn OFF the power supply and turn it ON again ing to the left mentioned procedure Press RESET button of the remote controller Y Repair the failure parts Deleting the memorized abnormal condition After repairing the unit recall the failure mode again according to Setting up the failure mode recall function 11 2 1 Press OPERATE STOP ON OFF button of the remote controller the set temperature is displayed with x3 The information regarding whether the connected outdoor unit is a low standby
26. seconds OFF 4 way valve Pipe temperature The 4 way valve does not work properly The indoor coil thermistor detects an abnormal temperature Refer to 11 5 6 Check of R V coil Replace the inverter P C board 17 time flash 2 5 seconds OFF Outdoor refrigerant System abnormality A closed valve and air trapped in the refrigerant circuit are detected based on the temperature sensed by the indoor and outdoor thermistors and the current of the compressor eCheck for a gas leak in a connecting piping etc Check the stop valve Refer to 11 5 Check of outdoor refrigerant circuit Outdoor unit stops and restarts 3 minutes later is repeated 2 time flash 2 5 seconds OFF Overcurrent protec tion Large current flows into power module 1C700 KJ25 35 IGBT module 1C700 KJ50 Reconnect the connector of the compressor Refer to 11 5 How to check in verter compressor eCheck the stop valve 3 time flash 2 5 seconds OFF Discharge tempera ture overheat pro tection Temperature of discharge temperature thermistor exceeds 116 C compressor stops Compressor can restart if discharge temperature thermistor reads 100 C or less 3 minutes later eCheck the refrigerant circuit and the refrigerant amount Refer to 11 5 Check of LEV 4 time flash 2 5 seconds OFF Fin temperature P C board tem perature thermistor overheat protection Temperature of fin
27. 0 KJ25 35 IGBT module IC700 KJ50 Reconnect the compressor connector Refer to 11 5 How to check inverter compressor eCheck the stop valve Compressor synchronous abnormality Compressor start up failure protection 12 time flash 2 5 seconds OFF Waveform of compressor current is distorted Reconnect the compressor connector Refer to 11 5 How to check inverter compressor 5 time flash 2 5 seconds OFF Discharge temperature Temperature of discharge temperature thermistor exceeds 116 C compressor stops Compressor can restart if discharge temperature thermistor reads 100 C or less 3 minutes later eCheck the refrigerant circuit and the refrigerant amount Refer to 11 5 Check of LEV 6 time flash 2 5 seconds OFF High pressure Temperature indoor coil thermistor exceeds 70 C in HEAT mode Temperature defrost thermistor exceeds 70 C in COOL mode Check the refrigerant circuit and the refrigerant amount eCheck the stop valve 7 time flash 2 5 seconds OFF Fin temperature P C board temperature 7 time flash 2 5 seconds OFF Temperature of fin temperature thermistor on the inverter P C board exceeds 75 86 C KJ25 35 75 80 C KJ50 or temperature of P C board temperature thermistor on the inverter P C board exceeds 72 85 C KJ25 35 70 75 C KJ50 eCheck around the outdoor unit eCheck the outdoor unit air passage R
28. 0 100 150 0 50 100 150 The operational frequency The operational frequency The operational frequency The operational frequency of compressor Hz of compressor Hz of compressor Hz of compressor Hz 8 3 HOW TO OPERATE FIXED FREQUENCY OPERATION lt Test run operation gt Press EMERGENCY OPERATION switch to start COOL or HEAT mode COOL Press once HEAT Press twice Test run operation starts and continues to operate for 30 minutes Compressor operates at rated frequency in COOL mode or 58 Hz in HEAT mode Indoor fan operates at High speed After 30 minutes test run operation finishes and EMERGENCY OPERATION starts operation frequency of compressor varies To cancel test run operation EMERGENCY OPERATION press EMERGENCY OPERATION switch or any button on remote controller OBH695 E 8 4 OUTDOOR LOW PRESSURE AND OUTDOOR UNIT CURRENT COOL operation Dry bulb temperature C Relative humidity Both indoor and outdoor unit are under the same temperature 20 50 humidity condition 25 60 Operation TEST RUN OPERATION Refer to 8 3 70 Outdoor low pressure MUFZ KJ25VE MUFZ KJ35VE MUFZ KJ50VE 0 8 0 7 T T T gt o F 06 9 9 9 0 5 0 4 5 0 3 15 20 25 30 35 15 20 25 30 35 50 60 70 50 60 70 Ambient temperature C Ambient temperature C Ambient temperature C Ambient humidity Ambient humidity 96 Ambient humidity NOTE
29. 68 Flared connection Strainer Muter EY Strainer 100 100 R V coil 1 heating ON S Capillary tube cooling OFF 04 0 02 4 100 Refrigerant pipe 26 35 gt Refrigerant flow in cooling with heat insulator Refrigerant flow in heating OBH695 E MAX REFRIGERANT PIPING LENGTH and MAX HEIGHT DIFFERENCE Refrigerant piping m Piping size O D mm Max Length A Max Height difference B Gas Liquid Model MUFZ KJ25 35 20 12 9 52 6 35 MUFZ KJ50 30 15 12 7 6 35 Indoor unit Max Height difference B Max Length A Outdoor unit ADDITIONAL REFRIGERANT CHARGE R410A g Outdoor unit Refrigerant piping length one way precharged 10m 11m 12m 13m MUFZ KJ25 35 1 100 90 120 150 180 Calculation X g 30 g m x Refrigerant piping length m 7 Model Outdoor unit Refrigerant piping length one way precharged 10m 15m 20m 25m MUFZ KJ50 1 500 60 160 260 360 Model Calculation X g 20 g m x Refrigerant piping length m 7 OBH695 n 8 PERFORMANCE CURVES MUFZ KJ25VE MUFZ KJ35VE MUFZ KJ50VE The standard specifications apply only to the operation of the air conditioner under normal conditions Since operating condi tions vary according to the areas where these units are installed the following information has been provided to clarify the operating characterist
30. SHF INPUT Q SHC SHC SHF INPUT 2 86 2 76 0 53 1288 2 34 2 26 0 41 1330 NOTE Q Total capacity kW SHF Sensible heat factor DB Dry bulb temperature SHC Sensible heat capacity kW INPUT Total power input W WB Wet bulb temperature OBH695 2m PERFORMANCE DATA COOL operation at Rated frequency MUFZ KJ50VE CAPACITY 5 0 kW SHF 0 71 OUTDOOR DB C SHC 35 SHF INPUT INPUT 1400 W 40 SHC SHF INPUT Q 46 SHC SHF INPUT NOTE Q Total capacity kW SHC Sensible heat capacity kW OBH695 SHF Sensible heat factor INPUT Total power input W 21 DB Dry bulb temperature WB Wet bulb temperature PERFORMANCE DATA HEAT operation at Rated frequency MUFZ KJ25VE CAPACITY 3 4 kW INPUT 770 W OUTDOOR WB C INDOOR 5 DB C INPUT Q INPUT 15 678 732 21 708 762 26 747 801 MUFZ KJ35VE CAPACITY 4 3 kW INPUT 1100 W OUTDOOR WB C INDOOR DB C 0 5 INPUT Q INPUT 15 968 1045 21 1012 1089 26 1067 1144 NOTE Q Total capacity kW INPUT Total power input W DB Dry bulb temperature WB Wet bulb temperature MUFZ KJ50VE CAPACITY 5 8 kW INPUT 1500 W OUTDOOR WB C INDOOR DB C 15 21 26 NOTE Q Total
31. T 2O Oi o 26 BE 252 B oO 5 U Z o3 Psg SES 35 88 o 206 9 20 gt 5 Defrost thermistor RT61 Ambient temperature thermistor RT65 Outdoor heat exchanger temperature thermistor RT68 Discharge temperature thermistor RT62 0 Resistance kQ ao 20 30 40 50 60 70 80 90 100 110 120 Temperature C 10 0 10 Temperature C OBH695 45 Fin temperature thermistor RT64 E E E E E Temperature C MUFZ KJ50VE Fuse F601 T3 15AL250V R V coil CN602 Heater CN601 230 VAC 230 VAC Signal of out door fan motor CN931 LEV connector CN724 Output to drive outdoor fan motor CN932 LED 4 Defrost thermistor big RT61 CN671 A Discharge temperature thermistor RT62 CN671 Jd Outdoor heat exchanger HM temperature thermistor RT68 CN671 tl Ambient temperature W thermistor RT65 Fuse F901 T3 15AL250V Fuse F880 T3 15AL250V thermistor RT64 CN673 Jumper wire for changing defrost setting JS Jumper wire for JP715 pre heat control hs m setting JK 325 370 VDC 3 d JP30 x To relay P C board CN680 CN681 Fo M Poe bs Defrost thermistor RT61 Ambient temperature thermistor RT65 0 Outdoor heat exchanger temperature thermistor RT68 5 CLIE
32. ash 2 5 seconds OFF Indoor outdoor communication receiving error Any signals from the inverter P C board cannot be received normally for 3 minutes Refer to 11 5 How to check miswiring and serial signal error Indoor outdoor communication receiving error Although the inverter P C board sends signal 0 signal 1 has been received 30 consecutive times Refer to 11 5 How to check miswiring and serial signal error 2 time flash 2 5 seconds OFF Outdoor power system Overcurrent protection cut out operates 3 consecutive times within 1 minute after the compressor gets started Reconnect the connectors Refer to 11 5 How to check inverter compressor eCheck the stop valve 3 time flash 2 5 seconds OFF Discharge temperature thermistor Defrost thermistor 1 time flash every 2 5 seconds Fin temperature thermistor 3 time flash 2 5 seconds OFF P C board temperature thermistor 4 time flash 2 5 seconds OFF Ambient temperature thermistor 2 time flash 2 5 seconds OFF Outdoor heat exchanger temperature thermistor Thermistor shorts or opens during compressor running Refer to 11 5 Check of outdoor thermistors Defective the outdoor thermistors can be identified by checking the blinking pattern of LED 4 time flash 2 5 seconds OFF Overcurrent 11 time flash 2 5 seconds OFF Large current flows into power module 1C70
33. bout 70 W Pre heat control setting lt JK gt ON To activate the pre heat control cut JK wire of the inverter P C board OFF To deactivate the pre heat control solder JK wire of the inverter P C board Refer to 11 6 1 NOTE When the inverter P C board is replaced check the jumper wires and cut solder them if necessary OBH695 7 11 TROUBLESHOOTING MUFZ KJ25VE MUFZ KJ35VE MUFZ KJ50VE 11 1 1 2 CAUTIONS ON TROUBLESHOOTING Before troubleshooting check the following 1 Check the power supply voltage 2 Check the indoor outdoor connecting wire for miswiring Take care of the following during servicing 1 Before servicing the air conditioner be sure to turn OFF the main unit first with the remote controller and then after confirming the horizontal vane is closed turn OFF the breaker and or disconnect the power plug 2 Be sure to turn OFF the power supply before removing the front panel the cabinet the top panel and the electronic control P C board 3 When removing the electrical parts be careful of the residual voltage of smoothing capacitor 4 When removing the electronic control P C board hold the edge of the board with care NOT to apply stress on the components 5 When connecting or disconnecting the connectors hold the housing of the connector DO NOT pull the lead wires lt Incorrect gt lt Correct gt Lead wiring Housing point 3 T
34. crews of the cabinet 9 Remove the cabinet 10 Remove the screws of the back panel 11 Remove the back panel Photo 2 Screw of the back panel Screws of the top panel Screws of the cabinet 1 D 1 1 1 Screws of the Scr ws of the cabinet cabinet Screws of the cabinet S f th crew of the Screws of the BELT el valve cover service panel acK p 51 OBH695 OPERATING PROCEDURE PHOTOS 2 Removing the inverter assembly inverter P C board and relay P C board 1 Remove the cabinet and panels Refer to 1 2 Disconnect the lead wire to the reactor and the following con nectors lt Inverter P C board gt CN602 R V coil CN931 CN932 Fan motor CN671 Defrost thermistor discharge temperature thermistor and outdoor heat exchanger temperature thermistor CN672 Ambient temperature thermistor CN724 LEV 3 Remove the compressor connector 4 Remove the screws fixing the relay panel 5 Remove the relay panel 6 Remove the earth wires and the lead wires of the inverter P C board 7 Remove the screws of the P B support 8 Remove the inverter P C board from the relay panel 9 Disconnect the following connectors lt Relay P C board gt CN60 Terminal block CN680 Inverter P C board TAB65 Inverter P C board TB71 10 Remove the screws fixing the P B holder 11 Remove the relay P C board from the P B holder 3 Removing R V coil 1 Remov
35. ction 11 time flash 2 5 seconds Bus bar voltage DC 8 time flash 2 5 seconds OFF Bus bar voltage of inverter cannot be detected normally OFF Each phase current of compressor 9 time flash 2 5 seconds OFF Each phase current of compressor cannot be detected normally Refer to 11 5 How to check inverter compressor O 14 time flash or more Stop valve Closed valve 14 time flash 2 5 seconds OFF Closed valve is detected by compressor current eCheck the stop valve 2 5 seconds OFF 4 way valve Pipe temperature 16 time flash 2 5 seconds OFF The 4 way valve does not work properly The indoor coil thermistor detects an abnormal temperature eCheck the 4 way valve Replace the inverter P C board abnormality Outdoor refrigerant system 17 time flash 2 5 seconds OFF A closed valve and air trapped in the refrigerant circuit are detected based on the temperature sensed by the indoor and outdoor thermistors and the current of the compressor eCheck for a gas leak in a connecting piping etc Check the stop valve Refer to 11 5 Check of outdoor refrigerant circuit NOTE Blinking patterns of this mode differ from the ones of TROUBLESHOOTING CHECK TABLE 11 3 OBH695 29 11 3 TROUBLESHOOTING CHECK TABLE Symptom LED indication Abnormal point Condition Condition Remedy Outdoor unit
36. e terminal pins of the connector although no signal is being transmitted to R V coil Check if CN602 is connected Unit operates COOL mode even if it is set to HEAT mode Disconnect connector between the compressor and the IGBT module 1C700 Turn ON the power supply and press EMERGENCY OPERATION switch twice HEAT mode Is there 230 VAC between CN602 and on the inverter P C board 3 minutes N after the power supply is turned ON Replace the inverter P C board Yes Replace the 4 way valve the 4 way valve Unit operates HEAT mode even if it is set to COOL mode Disconnect connector between the the IGBT modul Andie Is there 230 VAC between CN602 and 1C700 th ter P C board 3 t Replace the inverter Turn ON the power supply and on the inverter oard 3 minutes Yes P C board press EMERGENCY OPERATION after the power supply is turned ON Switch once COOL mode No Replace the 4 way valve OBH695 i D Check of outdoor fan motor Disconnect the connectors CN931 and CN932 from the inverter P C board Check the connection between the connector CN931 and CN932 Is the resistance between each ter minal of outdoor fan motor normal Refer to 11 4 Yes i No Disconnect CN932 from the inverter P C board and turn on the power supply Rotate the outdoor fan motor manually and measure the voltage o
37. e the cabinet and panels Refer to 1 2 Disconnect the following connector lt Inverter P C board gt CN602 coil 3 Remove the R V coil 52 OBH695 Photo 3 Inverter P C board Screw of the relay panel Photo 4 Screws of the Earth wires relay panel Screws of Relay Screw of the P B P C board the P B support holder Screw of the Brazed parts of 4 way valve OPERATING PROCEDURE PHOTOS 4 Removing the discharge temperature thermistor defrost thermistor outdoor heat exchanger tempera ture thermistor and ambient temperature thermistor 1 Remove the cabinet and panels Refer to 1 2 Disconnect the lead wire to the reactor and the following connectors lt Inverter P C board gt CN671 Defrost thermistor discharge temperature thermis tor and outdoor heart exchanger temperature ther mistor CN672 Ambient temperature thermistor 3 Pull out the discharge temperature thermistor from its hold er Photo 7 4 Pull out the defrost thermistor from its holder 5 Pull out the outdoor heat exchanger temperature thermistor from its holder 6 Pull out the ambient temperature thermistor from its holder Removing outdoor fan motor 1 Remove the top panel cabinet and service panel Refer to 1 2 Disconnect the following connectors lt Inverter P C board gt CN931 and CN932 Fan motor 3 Remove the propeller 4 Remove the screws fixing the fan motor
38. efer to 11 5 0 Check of outdoor fan motor 8 time flash 2 5 seconds OFF Outdoor fan motor Outdoor fan has stopped 3 times in a row within 30 seconds after outdoor fan start up Refer to 11 5 0 of outdoor fan motor Refer to 11 5 0 of inverter P C board 9 time flash 2 5 seconds OFF Nonvolatile memory data 5 time flash 2 5 seconds OFF Nonvolatile memory data cannot be read properly Replace the inverter P C board Power module 1 700 KJ25 35 IGBT module 1C700 KJ50 6 time flash 2 5 seconds OFF The interface short circuit occurs in the output of the power module 1 700 KJ25 35 IGBT module 1 700 KJ50 The compressor winding shorts circuit Refer to 11 5 How to check inverter compressor 10 time flash 2 5 seconds OFF Discharge temperature Temperature of discharge temperature thermistor has been 50 C or less for 20 minutes Refer to 11 5 Check of LEV Check the refrigerant circuit and the refrigerant amount NOTE Blinking patterns of this mode differ from the ones of TROUBLESHOOTING CHECK TABLE 11 3 OBH695 28 Left lamp of the OPERATION INDICATOR lamp Indoor unit Abnormal point Failure mode protection LED indication Outdoor P C board Condition Remedy Indoor outdoor unit failure mode recall function Outdoor unit failure mode recall fun
39. el LTT i Screws 6 Remove the screws fixing the cabinet ofthe 7 Remove the cabinet 8 Remove the screws fixing the back panel 9 Remove the back panel Screws of Serice the cabinet panel Photo 2 Screws of the terminal block support and the back panel Screw of the cabinet Screw of the service panel Direction to pro Screws of the cabinet OBH695 i OPERATING PROCEDURE PHOTOS 2 Removing the inverter assembly inverter P C board 1 Remove the cabinet and panels Refer to 1 2 Disconnect the lead wire to the reactor and the following con nectors lt Inverter P C board gt CN721 R V coil CN931 CN932 Fan motor CN641 Defrost thermistor and discharge temperature ther mistor CN643 Ambient temperature thermistor CN644 Outdoor heat exchanger temperature thermistor CN724 LEV 3 Remove the compressor connector CN61 4 Remove the screws fixing the heat sink support and the sep arator 5 Remove the fixing screws of the terminal block support and the back panel 6 Remove the inverter assembly 7 Remove the screw of the earth wire and screw of the termi nal block support 8 Remove the heat sink support from the P C board support 9 Remove the screw of the inverter P C board and remove the inverter P C board from the P C board support Removing R V coil 1 Remove the cabinet and panels Refer to 1 2 Disc
40. er probes and start the emergency operation Y When the emergency operation starts does the rated voltage occur for 2 IE between indoor terminal block S2 and S3 Check for miswiring broken wires and loose wire connection between the power supply and outdoor terminal block S1 and between the power supply and outdoor terminal block S2 yes No Does the left lamp of the OPERA TION INDICATOR lamp on the indoor unit blink continuously 6 minutes af No Does the outdoor LED light up ter the emergency operation starts y Does the outdoor LED blink 6 No times Yes between indoor terminal block S2 and 53 Yes is DC 6V or more occur Turn the power supply OFF Replace the indoor electronic control P C board OBH695 Y Yes Confirm that the thermostat is OFF and wiring is not loose Replace the outdoor inverter board 1 Replace the outdoor inverter P C board x1 Replace the indoor electronic control P C board 1 Electric charge may remain immediately after the power supply is turned OFF Perform the procedure after 3 minutes MUFZ KJ50 Turn the power supply OFF NOTE Refer to the indoor unit service manual Is there rated voltage in the power supply Check the power supply Yes No Check for incorrect indoor outdoor connecting wiring
41. f CN931 Between 1 and 5 Between 2 and 5 Between 3 and 5 Y lt Fixed to either 5 VDC the voltage between each terminal become 5 0 No N VDC repeatedly Yes Y lt No Does the outdoor fan motor rotate smoothly Yes Y Y Replace the outdoor fan motor Replace the inverter P C board OBH695 r J Check of power supply 1 700 MUFZ KJ25 35 IGBT module 1 700 MUFZ KJ50 Turn ON power supply and press EMERGENCY OPERATION switch Disconnect the connector between the compressor and the power module Rectify indoor outdoor connecting wire Yes Is there voltage 230 VAC Replace the indoor orate lamp on the indoor No between the indoor terminal No electronic control P C gat Up block 1 and S2 board yo Is there bus bar voltage 260 370 ML on p Replace the inverter between JP715 and JP30 Yes Refer 1 dene No board MUFZ KJ50 on the inverter P C board Refer to 11 6 1 es No If light up OK Check the electric parts in main circuit If flash refer to 11 3 260 370 VDC OF Inverter P C board Solder side MUFZ KJ25 35 JP30 JP715 325 370 VDC MUFZ KJ50 OBH695 K Check of LEV Expansion valve ON the power supply UN P
42. f lead wire F TlFZ KJ25 35VE MUFZ KJ50VE RED BLK BLK WHT WHT RED 12 16 12 17 WHT RED BLK R V coil 2154 Measure the resistance using a tester Temperature 10 40 C Normal kQ MUFZ KJ25 35VE MUFZ KJ50VE 1 41 2 00 1 19 1 78 Expansion valve coil LEV OBH695 Measure the resistance using a tester Temperature 10 40 C Normal Q MUFZ KJ25 35 50VE Color of lead wire RED ORN RED WHT RED BLU RED YLW 37 54 32 11 5 TROUBLESHOOTING FLOW How to check inverter compressor Disconnect the connector between the compressor and the power module IC 700 MUFZ KJ25 35 IGBT module IC700 MUFZ KJ50 Y Check the voltage between terminals See 11 5 Check of open phase y Are the voltages balanced No Replace the inverter P C board Yes Check the compressor ren See 11 5 Check of compressor Check of open phase e With the connector between the compressor and the power module IC700 MUFZ KJ25 35 IGBT module IC700 MUFZ KJ50 disconnected activate the inverter and check if the inverter is normal by measuring the voltage balance between the terminals Output voltage is 50 130 V The voltage may differ according to the tester lt lt Operation method Start cooling or heating opera
43. failure mode recall function after it is set up otherwise the unit cannot operate properly 2 If the abnormal condition is not deleted from the memory the last abnormal condition is kept memorized X2 Blinking pattern when the indoor unit is abnormal Blinking at 0 5 Blinking at 0 5 4 gt lt 4 gt OFF gt 1 4 O 45 O gt i Beeps Beeps x Beeps Repeated cycle Repeated cycle l Repeated cycle uc 3X3 Blinking pattern when the outdoor unit is abnormal Te Blinking at 0 5 Blinking at 0 5 2 5 second OFF 3 second ON second interval 2 5 second OFF 3 second ON second interval lt gt lt j gt lt p gt lt gt lt p gt lt gt NS i rr r OFF gt gt lt 4 gt 7 4 gt gt gt No beep Beeps gt No beep i Beeps 1 Repeated cycle Repeated cycle OBH695 5 3 Repeated cycle 2 Flow chart of the detailed outdoor unit failure mode recall function Operational procedure The outdoor unit might be abnormal Check if the outdoor unit is abnormal according to the following procedures Y Make sure that the remote controller is set to the failure mode recall function Y With the remote controller headed towards the indoor unit press TEMP 1 Regardless of normal or abnormal condition 2 short button to adjust the set temperature to 25 C 1 beeps are emitted as the signal is
44. for the electromagnetic noise 4 Press OPERATE STOP ON OFF button on the remote controller for power OFF when the outdoor unit stops but the indoor outdoor communication still runs on In this situation check for the electromagnetic noise OBH695 11 6 TEST POINT DIAGRAM AND VOLTAGE 1 Inverter P C board MUFZ KJ25VE MUFZ KJ35VE Smoothing Smoothing R V coil DB61 capacitor capacitor CN721 Back side of unit C62 C61 230 VAC Fuse F801 T3 15AL250V 230 VAC Fuse F701 T3 15AL250V D pg m A L3 em Fuse F901 BL TL or x mre T3 15AL250V PR P 0 hes es Ek a 4 T gt 13 1 Output to h 24 J 5 drive outdoor ing vu a OF fan motor n E HP E T U gre CN932 bi z O I 230 vac Output to f 8 drive E iij i 1 m j compressor pi A P E E SI Hola VR d usi S D Ld 1 LDU unn Ton qm Uam Mon LDV e f J piy t a LDW e d le D om bise z dh TR p es ENO p MNE Ls oe ww Xe E jor LED g i 5 S 5 E 5 5 Jumper wire for Jumper wire sr S 2 To E changing defrost for pre heat 22 2 59 on setting JS control setting Front side of unit 523 55 Sig 5 JK L
45. ics of the air conditioner under the conditions indicated by the performance curve 1 GUARANTEED VOLTAGE 198 264 V 50 Hz 2 AIR FLOW Air flow should be set at MAX 3 MAIN READINGS 1 Indoor intake air wet bulb temperature C WB 2 Indoor outlet air wet bulb temperature C WB Cooling 3 Outdoor intake air dry bulb temperature C DB 4 Total input W 5 Indoor intake air dry bulb temperature C DB 6 Outdoor intake air wet bulb temperature C WB Heating 7 Total input W Indoor air wet and dry bulb temperature difference on the left side of the following chart shows the difference between the indoor intake air wet and dry bulb temperature and the indoor outlet air wet and dry bulb temperature for your reference at service How to measure the indoor air wet and dry bulb temperature difference 1 Attach at least 2 sets of wet and dry bulb thermometers to the indoor air intake as shown in the figure and at least 2 sets of wet and dry bulb thermometers to the indoor air outlet The thermometers must be attached to the position where air speed is high Attach at least 2 sets of wet and dry bulb thermometers to the outdoor air intake Cover the thermometers to prevent direct rays of the sun N 3 Check that the air filter is cleaned 4
46. ling operation again Yes p The refrigerant gas amount may be 60 or less than the normal amount Identify where the gas is leaking from and fix the leak The operation has stopped to pre vent the diesel explosion caused by air trapped in the refrigerant circuit Close the stop valve and disconnect the power plug or turn the breaker OFF CAUTION Do not start the opera tion again to prevent hazards OBH695 Electromagnetic noise enters into TV sets or radios Is the unit earthed No gt Earth the unit Yes Is the distance between the antennas and the indoor unit within 3 m or is the distance between the antennas and the Yes outdoor unit within 3 m No Extend the distance between the antennas and the indoor unit and or the antennas and the outdoor unit Is the distance between the TV sets or radios and the indoor unit within 1 m or is the distance between the TV sets Yes radios and the outdoor unit within 3 m No Extend the distance between the TV sets and or radios and the indoor unit or the TV sets or radios and the outdoor unit Are the antennas damaged Is the coaxial cable damaged Replace or repair the antenna Is there any poor contact in the anten Yes Replace or repair the coaxial cable na wiring Is the indoor outdoor connecting wire Extend the distance between the indoor o
47. ndicators on the LCD screen shown in the right figure are all displayed Then release the but tons Y Press OPERATE STOP ON OFF button of the remote controller the set temperature is displayed with the remote controller headed towards the indoor unit 7X1 Mon Tue Wed Thu Fri Sat Sun SET JCLOCKO ON AM PM PM 3X1 Regardless of normal or abnormal condition T2349 BE BE HBSBI a short beep is emitted once the signal is y received Does the left lamp of the OPERATION INDICATOR lamp on Indoor unit is normal the indoor unit blink at the interval of 0 5 seconds But the outdoor unit might be abnormal because there are some abnor Blinks Either indoor or outdoor unit is abnormal Beep is emit No malities that cannot be recalled with this way ted at the same timing as the blinking of the left lamp of OFF Check if the outdoor unit is abnormal according to the detailed outdoor the OPERATION INDICATOR lamp X2 unit failure mode recall function Refer to 11 2 2 Yes NOTE It takes up to 1 minute to indicate the outdoor unit abnormality Judgment of indoor outdoor abnormality w Blinks Even if the OPERATION INDICATOR lamp is not lighting keep checking Before blinking does the left lamp of the OPERATION INDI at least 1 minute or longer CATOR lamp stay ON for 3 seconds Stays ON for 3 seconds without beep Yes The outdoor unit is abnormal No y Y The indoor unit is abnormal The outdoor unit is abnormal Check the blinking pat
48. nect the compressor and activate the inverter Then measure the time until the inverter stops due to over current 10700 failure lt lt Operation method gt gt 2 seconds Ca winding short Start heating or cooling operation by pressing EMERGENCY OPERATION switch on the indoor unit TEST RUN OPERATION NM avoit Refer to 8 3 Starting defect lt lt Measurement gt gt Measure the time from the start of compressor to the stop of Abnormal compressor due to overcurrent Poor contact 10 seconds Inverter P C board defect Disconnected connector Abnormal Refrigerant circuit defect Closed valve 10 minutes Normal Check of compressor start failure Confirm that O is normal Electrical circuit check Contact of the compressor connector Output voltage of inverter P C board and balance of them See 11 5 Q Direct current voltage between DB61 and MUFZ KJ25 35 JP715 and JP30 MUFZ KJ50 on the inverter P C board Voltage between outdoor terminal block 51 52 Does the compressor run for 10 seconds or Check the refrigerant circuit more after it starts Yes Check the stop valve After the compressor is heated with a drier does the compressor start x1 No Replace the compressor Yes 1 Heat the compressor with a drier for about 20 minutes Do not recover refrigerant gas while heating Compressor start failu
49. onnect the following connectors lt Inverter P C board gt CN721 R V coil 3 Remove R V coil Removing the discharge temperature thermistor defrost thermistor outdoor heat exchanger tempera ture thermistor and ambient temperature thermistor 1 Remove the cabinet and panels Refer to 1 2 Disconnect the lead wire to the reactor and the following con nectors Inverter P C board CN641 Defrost thermistor and discharge temperature ther mistor CN643 Ambient temperature thermistor CN644 Outdoor heat exchanger temperature thermistor 3 Pull out the discharge temperature thermistor from its holder 4 Pull out the defrost thermistor from its holder Photo 6 5 Pull out the outdoor heat exchanger temperature thermistor from its holder Photo 6 6 Pull out the ambient temperature thermistor from its holder 49 OBH695 Photo 3 Screws of the heat sink Screws of the terminal block support and the separator support and the back panel Photo 4 Inverter assembly Screw of the Terminal block support 4 Heat sink Heat sink support P C board F support Terminal block support N Q Screw of the Screw of the inverter P C board earth wire Screw of the R V coil Discharge temperature thermistor OPERATING PROCEDURE PHOTOS 5 Removing outdoor fan motor 1 Remove the cabinet and panels Refer to 1 2 Disconnect the following connectors lt Inverter P C
50. out that thermistor is performed 30 Refer to 11 5 Check of outdoor thermistors Abnormal point Condition Outdoor unit 7 time flash Low discharge tem Temperature of discharge temperature thermistor has been Refer to 11 5 Check of LEV operates 2 5 seconds OFF perature protection 50 C or less for 20 minutes eCheck the refrigerant circuit and the refrigerant amount 8 time flash MUFZ KJ25 35 The overcurrent flows into PFC Power factor correction This is not malfunction PAM pro 2 5 seconds OFF PAM protection 1C820 or the bus bar voltage reaches 394 V or more PAM tection will be activated in the fol PAM Pulse Ampli stops and restarts lowing cases tude Modulation 1 Instantaneous power voltage drop Short time power failure 2 When the power supply voltage is high MUFZ KJ50 Zero cross signal cannot be detected elt occurs with following cases Zero cross detecting 1 Instantaneous power voltage circuit drop Short time power failure 2 Distortion of primary voltage Refer to 11 5 O Check of power supply 9 time flash Inverter check mode The connector of compressor is disconnected inverter check Check if the connector of the com 2 5 seconds OFF mode starts pressor is correctly connected Refer to 11 5 How to check inverter compressor Symptom LED indication Condition Remedy NOTE 1 The location of LED is illustrated at the right figure
51. re Activate pre heat control Refer to 10 2 PRE HEAT CONTROL SETTING Heating part OBH695 m G Check of outdoor thermistors Disconnect the connector of thermistor in the Inverter P C board see below table and measure the resistance of thermistor Y 7 Is the resistance of thermistor normal 2 R Refer to 11 6 1 board yes Reconnect the connector of thermistor Turn ON the power supply and press EMERGENCY OPERATION switch Does the unit operate for 10 minutes or more without showing thermistor abnormality No Replace the inverter P C board yes OK Cause is poor contact MUFZ KJ25 35 Thermistor Connector Pin No Replace the thermistor except RT64 When RT64 is abnormal replace the inverter P C Defrost Between CN641 pin1 and pin2 Discharge temperature Between CN641 pin3 and pin4 Fin temperature Between CN642 pin1 and pin2 Ambient temperature Between CN643 pin1 and pin2 Outdoor heat exchanger temperature MUFZ KJ50 Thermistor Between CN644 pin1 and pin3 Connector Pin No Inverter P C board Defrost Between CN671 pin1 and pin2 Discharge temperature Between CN671 pin3 and pin4 Fin temperature Between CN673 pin1 and pin2 Ambient temperature Between CN672 pin1 and pin2 Outdoor heat e
52. reparation of the remote controller While pressing both OPERATION SELECT MODE button and TEMP button on the remote controller at the same time press RESET button First release RESET button Hold down the other two buttons for another 3 sec onds Make sure that the indicators on the LCD screen shown in the right figure are all displayed Then re F lease the buttons MITSUBISHI ELECTRIC m Press OPERATE STOP ON OFF button of the remote i JL 38 controller the set temperature is displayed with the remote controller headed towards the indoor unit X1 L lc CE t Gru Y 123480 00 00 00700 Expansion valve operates in full opening direction Y 7X1 Regardless of normal or abnormal condition a short beep Do you hear the expansion valve click is emitted once the signal is received Do you feel the expansion valve vibrate Yes on touching it No y Is LEV coil properly fixed to Properly fix the LEV coil to the expansion valve valve No the expansion Yes easure each voltage between connector pins of CN724 on the inverter P C board y 1 Pin Pind Does the resistance of LEV 2 Pin Pin coil have the characteristics gt 3 Pin Pin the inverter P C Refer to 11 4 4 Pin Pin Is there about 3 5 VAC between each
53. roubleshooting procedure 1 Check if the OPERATION INDICATOR lamp on the indoor unit is flashing on and off to indicate an abnormality To make sure check how many times the OPERATION INDICATOR lamp is flashing on and off before starting serv ice work 2 Before servicing check that the connector and terminal are connected properly 3 When the electronic control P C board seems to be defective check the copper foil pattern for disconnection and the components for bursting and discoloration 4 Refer to 11 2 and 11 3 OBH695 11 2 FAILURE MODE RECALL FUNCTION Outline of the function This air conditioner can memorize the abnormal condition which has occurred once Even though LED indication listed on the troubleshooting check table 11 3 disappears the memorized failure details can be recalled 1 Flow chart of failure mode recall function for the indoor outdoor unit Operational procedure The cause of abnormality cannot be found because the abnormality does not recur Setting up the failure mode recall function Turn ON the power supply lt Preparation of the remote controller gt While pressing OPERATION SELECT MODE button and TEMP button on the remote controller at the same time press RESET button First release RESET button Hold down the other two buttons for another 3 seconds Make sure that the i
54. rt time power failure KJ50 Refer to 11 5 Check of power supply KJ50 Refer to 11 5 How to check in verter compressor Outdoor unit operates 1 time flash 2 5 seconds OFF Frequency drop by current protection KJ25 35 When the input current exceeds approximately 10A KJ25 10 5A KJ35 compressor frequency lowers KJ50 Current from power outlet is nearing breaker ca pacity 3 time flash 2 5 seconds OFF Frequency drop by high pressure pro tection Temperature of indoor coil thermistor exceeds 55 C in HEAT mode compressor frequency lowers Frequency drop by defrosting in COOL mode Indoor coil thermistor reads 8 C or less in COOL mode com pressor frequency lowers The unit is normal but check the following Check if the indoor filters are clogged eCheck if the refrigerant is short Check if the indoor outdoor unit air circulation is short cycled 4 time flash 2 5 seconds OFF Frequency drop by discharge tempera ture protection Temperature of discharge temperature thermistor exceeds 111 C compressor frequency lowers Check the refrigerant circuit and the refrigerant amount Refer to 11 5 Check of LEV Refer to 11 5 Check of outdoor thermistors 5 time flash 2 5 seconds OFF OBH695 Outside temperature thermistor protec tion When the outside temperature thermistor shorts or opens protective operation with
55. temperature thermistor on the heat sink ex ceeds 75 86 C KJ25 35 75 80 C KJ50 or temperature of P C board temperature thermistor on the inverter P C board exceeds 72 85 C KJ25 35 70 75 C KJ50 eCheck around the outdoor unit Check the outdoor unit air passage Refer to 11 5 0 Check of outdoor fan motor 5 time flash 2 5 seconds OFF High pressure pro tection Indoor coil thermistor exceeds 70 C in HEAT mode Defrost thermistor exceeds 70 C in COOL mode Check the refrigerant circuit and the refrigerant amount Check the stop valve 8 time flash 2 5 seconds OFF Compressor syn chronous abnormal ity The waveform of compressor current is distorted Reconnect the connector of the compressor Refer to 11 5 How to check in verter compressor 10 time flash 2 5 seconds OFF Outdoor fan motor Outdoor fan has stopped 3 times in a row within 30 seconds after outdoor fan start up Refer to 11 5 Check of outdoor fan motor Refer to 11 5 Check of inverter P C board 12 time flash 2 5 seconds OFF Each phase current of compressor Each phase current of compressor cannot be detected nor mally Refer to 11 5 How to check in verter compressor 13 time flash 2 5 seconds OFF Bus bar voltage DC Bus bar voltage of inverter cannot be detected normally occurs with following case Instantaneous power voltage drop Sho
56. tern and identify the abnormal point by referring to the Check the blinking pattern and identify the abnormal point by referring to indoor unit failure mode table Refer to indoor unit service manual the outdoor unit failure mode table Refer to 11 2 3 Make sure to check at least two consecutive blinking cycles 2 Make sure to check at least two consecutive blinking cycles X3 Releasing the failure mode recall function Release the failure mode recall function by the following procedures Turn OFF the power supply and turn it ON again Press RESET button of the remote controller Repair the failure parts Deleting the memorized abnormal condition After repairing the unit recall the failure mode again according to Setting up the failure mode recall z function mentioned above x4 The information regarding whether the connected Press OPERATE STOP ON OFF button of the remote controller the set temperature is displayed outdoor unit is a low standby power model or a non low with the remote controller headed towards the indoor unit standby power model will also be initialized Press EMERGENCY OPERATION switch so that the memorized abnormal condition is deleted 4 Default compatible with a low standby power model Release the failure mode recall function according to Releasing the failure mode recall function mentioned above NOTE 1 Make sure to release the
57. tion perature thermistor Cooling High pressure protec tion OBH695 10 SERVICE FUNCTIONS MUFZ KJ25VE MUFZ KJ35VE MUFZ KJ50VE 10 1 CHANGE IN DEFROST SETTING 10 2 Changing defrost finish temperature lt JS gt To change the defrost finish temperature cut solder the JS wire of the outdoor inverter P C board Refer to 11 6 1 Jumper wire Defrost finish temperature C Soldered Initial setting 5 None Cut 10 PRE HEAT CONTROL SETTING PRE HEAT CONTROL MUFZ KJ25 35 When moisture gets into the refrigerant cycle it may interfere the start up of the compressor at low outside temperature The pre heat control prevents this interference The pre heat control turns ON when the discharge temperature thermis tor is 20 C or below When the pre heat control turns ON the compressor is energized About 50 W MUFZ KJ50 Prolonged low load operation in which the thermostat is OFF for a long time at low outside temperature 0 C or less may cause the following troubles To prevent those troubles activate the pre heat control 1 If moisture gets into the refrigerant cycle and freezes it may interfer the start up of the compressor 2 If liquid refrigerant collects in the compressor a failure in the compressor may occur The pre heat control turns ON when the compressor temperature is 20 C or below When the pre heat control turns ON the compressor is energized A
58. tion by pressing EMERGENCY OPERATION switch on the indoor unit TEST RUN OPERA TION Refer to 8 3 Measurement point gt gt At 3 points Measure AC voltage between the lead wires at 3 points BLK U WHT V BLK U RED W WHT V RED W NOTE 1 Output voltage varies according to power supply voltage 2 Measure the voltage by analog type tester 3 During this check LED of the inverter P C board flashes 9 times Refer to 11 6 1 O Check of compressor winding Is the compressor normal Yes Refer to 11 5 Check of compressor No Replace the compressor to 11 5 0 Check of compressor operation time Does the compressor operate continuously Yes No Refer to 11 5 Check of compressor start failure OBH695 d D Check of compressor winding e Disconnect the connector between the compressor and the power module IC700 MUFZ KJ25 35 IGBT module IC700 MUFZ KJ50 and measure the resistance between the compressor terminals Measurement point At 3 points BLK WHT BLK RED WHT RED lt lt Judgement gt gt Refer to 11 4 nnn Abnormal short Infinite Abnormal open NOTE Be sure to zero the ohmmeter before measurement X Measure the resistance between the lead wires at points Check of compressor operation time lt lt Judgement gt gt Compressor starts e Con
59. ts We will not be held responsible for mechanical failure system malfunction unit breakdown or accidents caused by failure to follow the instructions OBH695 1 TECHNICAL CHANGES z MUFZ KJ25VE MUFZ KJ35VE MUFZ KJ50VE a 1 New model z a 2 PART NAMES AND FUNCTIONS MUFZ KJ25VE MUFZ KJ35VE Air inlet back and side Air outlet Drain outlet MUFZ KJ50VE Airinlet back and side Piping ey AN Drain outlet ACCESSORIES MUFZ KJ25VE Model MUFZ KJ35VE MUFZ KJ50VE Drain socket 1 OBH695 i 3 SPECIFICATION Outdoor model MUFZ KJ25VE MUFZ KJ35VE MUFZ KJ50VE Power supply Single phase 230 V 50 Hz Cooling Heating Capacity Rated frequency Min Max 2 5 0 5 3 4 3 5 0 5 3 7 5 0 1 6 5 7 3 4 1 2 4 6 4 3 1 2 5 8 5 8 2 2 8 2 Breaker Capacity 16 Cooling Heating Power input 1 Set 540 900 1 400 770 1 100 1 500 Cooling Heating Running current 1 Set 2 7 4 2 6 2 3 7 5 0 6 7 Cooling Heating Electrical data Power factor 1 Set 87 93 98 91 94 97 Starting current 1 Set A 3 7 5 0 6 7
60. utdoor of the air conditioner and the wiring of gt connecting wire of the air conditioner and the wir the antennas close Yes ing of the antennas Even if all of the above conditions are fulfilled the electromagnetic noise may enter depending on the electric field strength r the installation condition combination of specific conditions such as antennas or wiring Check the following before asking for service 1 2 3 4 Devices affected by the electromagnetic noise TV sets radios FM AM broadcast shortwave Channel frequency broadcast station affected by the electromagnetic noise Channel frequency broadcast station unaffected by the electromagnetic noise Layout of indoor outdoor unit of the air conditioner indoor outdoor wiring earth wire antennas wiring from antennas receiver Electric field intensity of the broadcast station affected by the electromagnetic noise Presence or absence of amplifier such as booster Operation condition of air conditioner when the electromagnetic noise enters in 1 Turn OFF the power supply once and then turn ON the power supply In this situation check for the electromagnetic noise 2 Within 3 minutes after turning ON the power supply press OPERATE STOP ON OFF button on the remote controller for power ON and check for the electromagnetic noise 3 After a short time 3 minutes later after turning ON the outdoor unit starts running During operation check
61. xchanger temperature OBH695 Between CN671 pind and 35 Inverter P C board Check of R V coil MUFZ KJ25 35 First of all measure the resistance of R V coil to check if the coil is defective Refer to 11 4 In case CN721 is disconnected or R V coil is open voltage is generated between the terminal pins of the connector although no signal is being transmitted to R V coil Check if CN721 is connected Unit operates COOL mode even if it is set to HEAT mode Disconnect connector between the ao and Me powermodule Is there 230 VAC between CN721 and nee Turn ON the power supply and press on the inverter board 3 minutes N P C board EMERGENCY OPERATION switch after the power supply is turned ON twice HEAT mode Yes Replace the 4 way valve the 4 way valve Unit operates HEAT mode even if it is set to COOL mode Disconnect connector between the dth dul Is there 230 VAC between CN721 and Turn ON the power supply and on the inverter P C board 3 minutes press EMERGENCY OPERATION after the power supply is turned ON switch once COOL mode No Replace the 4 way valve Replace the inverter Yes P C board MUFZ KJ50 First of all measure the resistance of R V coil to check if the coil is defective Refer to 11 4 In case CN602 is disconnected or R V coil is open voltage is generated between th

SERVICE MANUAL MUFZ-KJ25VE - A1 MUFZ-KJ35VE

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