Summary of the content on the page No. 1
OB427B-1.qxp 07.5.16 3:30 PM Page 1
Revision B:
•Remote controller model has been changed.
•RoHS PARTS LIST has been added.
SPLIT-TYPE, HEAT PUMP AIR CONDITIONERS
Please void OB427 REVISED EDITION-A.
INDOOR UNIT
No. OB427
REVISED EDITION-B
SERVICE MANUAL
Wireless type
Models
S1
MSH-A18ND -
S1
MSH-A24ND -
Outdoor unit service manual
MUH-A·ND Series (OB428)
CONTENTS
1. TECHNICAL CHANGES ····································2
2. PART NAMES AND FUNCTIONS······················2
3. SPECIFICATION··
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OB427B-1.qxp 07.5.17 7:35 AM Page 2 Revision A: • Parts No. of 10.PARTS LIST has been revised. Revision B: •Remote controller model has been changed. (KP0A ➔ KM04A) Both remote controllers can be used as alternative. •RoHS PARTS LIST has been added. 1 TECHNICAL CHANGES S1 S1 MSH-18TN - ➔ MSH-A18ND - S1 S1 MSH-24TN - ➔ MSH-A24ND - 1. Model name has been changed. 2. Grille design has been changed. 3. Unit size has been changed.(W 1,015a o H 320a o D 190a ➔ W 1,100a o H 325a o D 258a) 4. Ele
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OB427B-1.qxp 07.5.16 3:30 PM Page 3 REMOTE CONTROLLER MSH-A18ND MSH-A24ND Signal transmitting section Operation display section PM AM OPERATE /STOP (ON /OFF) button TOO TOO ON/OFF WARM COOL TEMPERATURE buttons Indication of remote controller model is on back. Open the front lid. CLOCK PM AM TOO TOO ON/OFF WARM COOL VANE button FAN SPEED CONTROL button FAN STOP (Horizontal vane button) I FEEL COOL OFF-TIMER button VANE START HEAT DRY ON-TIMER button MODE WIDE VANE HR. HR. butto
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OB427B-1.qxp 07.5.16 3:30 PM Page 4 3 SPECIFICATION Indoor model MSH-A18ND MSH-A24ND Function Cooling Heating Cooling Heating Single phase Single phase Power supply 220V, 60Hz 220V, 60Hz Capacity Air flow (High/Med./Low) 954/822/684 954/834/726 K /h 768/642/516 Running current A 0.28 0.37 Power input W 60 81 Power factor % 97 99 Model RC4N32-AA RC4V40-AA Current A 0.28 0.37 Winding WHT-BLK 205.5 WHT-BLK 138.2 " resistance (at 20:) BLK-RED 217.6 BLK-RED 159.0 Dimensions WOHOD mm 1,100O325O258
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OB427B-1.qxp 07.5.16 3:30 PM Page 5 4 OUTLINES AND DIMENSIONS Unit: mm MSH-A18ND MSH-A24ND INDOOR UNIT Installation plate Indoor unit 98 173 1068 98 414.5 414.5 173 Wall hole [75 258 5 Liquid line [ 6.35- 0.5m 1100 Air in Installation plate Gas line [ 12-0.43m { Insulation [ 50 O.D [ 32 I.D for MSH-A18ND Liquid line [ 9.52- 0.5m Gas line [ 12-0.43m { Insulation [ 50 O.D [ 32 I.D for MSH-A24ND 56 791 253 Drain hose [16 (Connected part O.D) Air out Insulation [28 58 19 Wireless remote controller
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OB427B-1.qxp 07.5.16 3:30 PM Page 6 5 WIRING DIAGRAM MSH-A18ND INDOOR UNIT CN RT12 112 TO OUTDOOR HIC1 CN UNIT RT11 111 CONNECTING TB CN201 BLK 12V 3 RED 3 GRY NR11 CN 3 121 YLW 2 N BLU BRN MF 1 1 C11 WHT F11 SR141 3 220V~ TAB12 2 BRN RED 4 CN211 CN CN CN 151 102 101 ELECTRONIC CONTROL P.C. BOARD 15 33 DISPLAY RECEIVER MV2 MV2 MV1 P.C.BOARD P.C.BOARD REMOTE CONTROLLER SYMBOL SYMBOL NAME NAME SYMBOL NAME C11 INDOOR FAN CAPACITOR MV1 VANE MOTOR (HORIZONTAL) RT12 INDOOR COIL THERMISTOR F11 FUSE (
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OB427B-1.qxp 07.5.16 3:30 PM Page 7 6 REFRIGERANT SYSTEM DIAGRAM Unit:mm MSH-A18ND MSH-A24ND INDOOR UNIT INDOOR UNIT Refrigerant pipe [15.88 Refrigerant pipe [12.7 (with heat insulator) (with heat insulator) Indoor coil Indoor coil Indoor thermistor Indoor thermistor RT12(main) heat RT12 heat exchanger exchanger Distributor Distributor Flared connection Flared connection Indoor coil thermistor RT13(sub) Room temperature thermistor RT11 Room temperature thermistor RT11 Flared connection Flared
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OB427B-1.qxp 07.5.16 3:30 PM Page 8 7 SERVICE FUNCTIONS MSH-A18ND MSH-A24ND 7-1. TIMER SHORT MODE For service, set time can be shortened by short circuit of JPG and JPS on the electronic control P.C. board. The time will be shortened as follows. Set time : 1 minute ➔ 1-second Set time : 3 minute ➔ 3-second (It takes 3 minutes for the compressor to start operation. However, the starting time is shortened by short circuit of JPG and JPS.) 7-2. P.C. BOARD MODIFICATION FOR INDIVIDUAL OPERATION A
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CN211 OB427B-1.qxp 07.5.16 3:30 PM Page 9 How to release “AUTO RESTART FUNCTION” 1Turn off the main power for the unit. 2Pull out the electronic control P.C. board, the receiver P.C. C11 board and the display P.C.board. (Refer to 9-2.) 3Solder jumper wire to JR07 on the indoor electronic control P.C. board. (Refer to 8-6.) CN201 TAB12 IC101 IC152 JR07 Operation 1If the main power has been cut, the operation settings remain. 2After the power is restored, the unit restarts automatically accordi
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OB427B-1.qxp 07.5.16 3:30 PM Page 10 8 TROUBLESHOOTING MSH-A18ND MSH-A24ND 8-1. Cautions on troubleshooting 1. Before troubleshooting, check the following: (1) Check the power supply voltage. (2) Check the indoor/outdoor connecting wire for mis-wiring. 2. Take care of the following during servicing (1) Before servicing the air conditioner, be sure to first turn off the remote controller to stop the main unit, and then after confirming the horizontal vane is closed, turn off the breaker and / o
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OB427B-1.qxp 07.5.16 3:30 PM Page 11 8-2. Instruction of troubleshooting Start Indoor unit Indoor unit Indoor unit operates. OPERATION INDICATOR operates. doesn't receive Outdoor unit lamp on the indoor unit is Outdoor unit the signal from doesn't operate flashing on and off. doesn't remote controller. normally. operate. Outdoor unit Outdoor unit Indoor unit Indoor unit Outdoor unit Unit doesn't operates when doesn't operates when doesn't operate doesn't operate the EMERGENCY stop
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OB427B-1.qxp 07.5.16 3:30 PM Page 12 8-3. Troubleshooting check table • The following indication applies regardless of shape of the indicator. • Before taking measures, make sure that the symptom reappears for accurate troubleshooting. When the indoor unit has started operation and the following detection method has detected an abnormality (the first detection after the power ON), the indoor electronic control P.C. board turns OFF the indoor fan motor with the OPERATION INDICATOR lamp flashi
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OB427B-1.qxp 07.5.16 3:30 PM Page 13 8-4. Trouble criterion of main parts MSH-A18ND MSH-A24ND Part name Check method and criterion Figure Room temperature Measure the resistance with a tester. (Part temperature 10˚C ~ 30˚C) thermistor (RT11) Normal Indoor coil thermistor (RT12(main), RT13(sub)) 8 k" ~ 20 k" Measure the resistance between the terminals with a tester. MSH-A18ND (Part temperature 10˚C ~ 30˚C) MAIN AUX Color of Normal Indoor fan motor(MF) FUSE lead wire MSH-A18ND MSH-A24ND WHT – B
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OB427B-1.qxp 07.5.16 3:30 PM Page 14 8-5. Troubleshooting flow When OPERATION INDICATOR lamp flashes 3-time. Indoor fan motor doesn’t operate. A Check of indoor fan motor Turn OFF the power supply. Check connector CN211 visually. No Yes No Is soldered point of the connector Are lead wires connected? Resolder it. correctly soldered? Yes Reconnect the lead wires. Disconnect lead wires from connector CN211 on the indoor electronic control P.C. board. Measure resistance between lead wires No.3 and
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OB427B-1.qxp 07.5.16 3:30 PM Page 15 The unit doesn’t operate with the remote controller. Also, the OPERATION INDICATOR lamp doesn’t light up by press- ing the EMERGENCY OPERATION switch. C Check of indoor electronic control P.C. board Check the both “parts side” and “pattern Varistor (NR11) side” of indoor electronic control P.C. board visually. Turn OFF the power supply. Remove indoor fan motor connector CN211 and vane motor connector CN151 from the indoor electronic Fuse (F11) control P
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OB427B-1.qxp 07.5.16 3:30 PM Page 16 When OPERATION INDICATOR lamp flashes ON and OFF in every 0.5-second. Outdoor unit doesn’t operate. D How to check mis-wiring w Short circuit of JPG and JPS on the indoor electronic control P.C. board enables self -check to be displayed in 3 seconds. Start • Turn ON the power supply. (outdoor unit) • Press EMERGENCY OPERATION switch once. After 3 minutes, mis-wiring is indicated (0.5-second ON, 0.5-second OFF) on OPERATION INDICATOR lamp on indoor un
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} OB427B-1.qxp 07.5.16 3:30 PM Page 17 8-6. Test point diagram and voltage MSH-A18ND MSH-A24ND Indoor electronic control P.C. board Fan motor power supply Power supply input } 220V AC } 5V DC + Fuse (F11) 250V AC 3.15A Room temperature ther- mistor(RT11) Indoor coil thermistor(RT12(main)) PS132 MSH-A24ND Indoor coil thermistor(RT13(sub)) Emergency operation switch Timer short mode point (JPS, JPG) (Refer to 7-1.) + Receiver P.C. board 12V DC Indoor coil thermistor(RT12(main), RT13(sub))
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OB427B-1.qxp 07.5.16 3:30 PM Page 18 9 DISASSEMBLY INSTRUCTIONS <"Terminal with locking mechanism" Detaching points> 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 c
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OB427B-1.qxp 07.5.16 3:30 PM Page 19 OPERATING PROCEDURE PHOTOS 3. Removing the electrical box Photo 3 Screws of the ground wire (1) Remove the front panel. (Refer to 1.) (2) Remove the electrical cover. (Refer to 2.) (3) Disconnect the connector of the indoor coil thermistor. (4) Disconnect the motor connector (CN211 and CN121) and the vane motor connector (CN151) on the electronic Screw of the control P.C. board. electrical cover (5) Remove the screws of ground wire. (6) Remove the fan moto
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OB427B-1.qxp 07.5.16 3:30 PM Page 20 10 PARTS LIST (non-RoHS compliant) MSH-A18ND MSH-A24ND 10-1. INDOOR UNIT STRUCTURAL PARTS 10-2. INDOOR UNIT HEAT EXCHANGER 1 2 11 3 9 4 8 (See 10-5.) 5 12 13 6 7 10-1. INDOOR UNIT STRUCTURAL PARTS Part number that is circled is not shown in the illustration. Q'ty/unit Symbol in Wiring NO. Part No. Part Name Remarks S1 S1 MSH-A18ND - MSH-A24ND - Diagram E02 527 970 1 INSTALLATION PLATE 1 1 2 E02 685 234 BOX 1 1 3 E02 888 000 1 1 Including No.4,5,6
