SERVICE MANUAL MUH-A18WV - MUH-A24WV - MUH-A30WV - E1. Wireless type Models HFC

Transcription

1 SPLIT-TYPE, HEAT PUMP AIR CONDITIONERS Revision A: Resistance of LEV (Expansion valve) has been modified. Power input and others have been added to SPECIFICATION. Method of check of R.V. coil has been modified. Please void OB322. SERVICE MANUAL Wireless type Models E MUH-A8WV - E MUH-A24WV - MUH-A30WV - E HFC utilized R40A. OB322 REVISED EDITION-A CONTENTS Indication of model name MUH-A8WV - E. TECHNICAL CHANGES 3 2. PART NAMES AND FUNCTIONS 6 3. SPECIFICATION 6 4. NOISE CRITERIA CURVES 8 5. OUTLINES AND DIMENSIONS 9 6. WIRING DIAGRAM 0 7. REFRIGERANT SYSTEM DIAGRAM 2 8. PERFORMANCE CURVES 5 9. MICROPROCESSOR CONTROL SERVICE FUNCTIONS 29. TROUBLESHOOTING DISASSEMBLY INSTRUCTIONS PARTS LIST 43 NOTE: This service manual describes technical data of outdoor units. As for indoor units MSH-A8WV- E, MSH-A24WV- E and MSH-A30V- E, refer to the service manual OB32.

2 Revision A: Resistance of LEV (Expansion valve) has been modified. (30.3 " ~ 37.0 " 4.0 " ~ 49.0 ") TROUBLESHOOTING has been partially modified. Power outlet, running current, power input and power factor have been added. SPECIFICATION has been partially modified. Method of check of R.V. coil has been modified. TROUBLESHOOTING has been partially modified.

3 TECHNICAL CHANGES MUH-8RV - E2 MUH-A8WV -. Refrigerant has changed. (R22 R40A) 2. Refrigerant system diagram has changed. Compressor, stop valve and 4-way valve have changed. Diameter of stop valve has changed. (Gas: [5.88 [2.7) Accumulator has removed and high pressure receiver has been added. 3. Oil separator has been added. MUH-24RV - E MUH-A24WV -. Dimension of outdoor unit has changed. 2. Refrigerant has changed. (R22 R40A) 3. Refrigerant system diagram has changed. Diameter of stop valve has changed. (Liquid: [9.52 [6.35) Accumulator has removed and high pressure receiver has been added. MUH-30RV - E MUH-A30WV -. Dimension of outdoor unit has changed. 2. Refrigerant has changed. (R22 R40A) 3. Refrigerant system diagram has changed. Accumulator has removed and high pressure receiver has been added. E E E INFORMATION FOR THE AIR CONDITIONER WITH R40A REFRIGERANT This room air conditioner adopts an HFC refrigerant (R40A) which never destroys the ozone layer. Pay particular attention to the following points, though the basic installation procedure is same as that for R22 conditioners. As R40A has working pressure approximate.6 times as high as that of R22, some special tools and piping parts/ materials are required. Refer to the table below. 2 Take sufficient care not to allow water and other contaminations to enter the R40A refrigerant during storage and installation, since it is more susceptible to contaminations than R22. 3 For refrigerant piping, use clean, pressure-proof parts/materials specifically designed for R40A. (Refer to 2. Refrigerant piping.) 4 Composition change may occur in R40A since it is a mixed refrigerant. When charging, charge liquid refrigerant to prevent composition change. Refrigerating Refrigerant oil New refrigerant Refrigerant R40A Composition (Ratio) HFC-32: HFC-25 (50%:50%) Refrigerant handling Pseudo-azeotropic refrigerant Chlorine t included Safety group (ASHRAE) A/A Molecular weight 72.6 Boiling point (:) -5.4 Steam pressure [25:](Mpa).557 Saturated steam density [25:](Kg/K) 64 Combustibility n combustible ODP w 0 GWP w2 730 Refrigerant charge method From liquid phase in cylinder Additional charge on leakage Possible Kind Incompatible oil Color n Smell n w :Ozone Destruction Parameter : based on CFC- w2 :Global Warmth Parameter : based on CO2 Previous refrigerant R22 R22 (00%) Single refrigerant Included A n combustible Gas phase Possible Compatible oil Light yellow n 3

4 Compressor New Specification Current Specification The incompatible refrigerating oil easily separates from refrigerant and is in the upper layer inside the suction muffler. Raising position of the oil back hole enables to back the Since refrigerant and refrigerating oil are compatible each, refrigerating oil backs to the compressor through the lower position oil back hole. refrigerating oil of the upper layer to flow back to the compressor. Suction muffler Suction muffler Compressor Oil back hole Refrigerating oil Compressor Oil back hole Refrigerant Refrigerating oil /Refrigerant NOTE : The unit of pressure has been changed to MPa on the international system of units(si unit system). The conversion factor is: (MPa [Gauge]) =0.2(kgf/f [Gauge]) Conversion chart of refrigerant temperature and pressure (MPa [Gauge]) R40A Saturated liquid pressure R22 NOTE : The unit of pressure has been changed to MPa on the international system of units(si unit system). The conversion factor is: (MPa [Gauge]) =0.2(kgf/f [Gauge]) (:).Tools dedicated for the air conditioner with R40A refrigerant The following tools are required for R40A refrigerant. Some R22 tools can be substituted for R40A tools. The diameter of the service port on the stop valve in outdoor unit has been changed to prevent any other refrigerant being charged into the unit. Cap size has been changed from 7/6 UNF with 20 threads to /2 UNF with 20 threads. R40A tools Can R22 tools be used? Description R40A has high pressures beyond the measurement range of existing Gauge manifold gauges. Port diameters have been changed to prevent any other refrigerant from being charged into the unit. Charge hose Gas leak detector Hose material and cap size have been changed to improve the pressure resistance. Dedicated for HFC refrigerant. Torque wrench 6.35 mm and 9.52 mm 2.7 mm and 5.88 mm Flare tool Flare gauge New Clamp bar hole has been enlarged to reinforce the spring strength in the tool. Provided for flaring work (to be used with R22 flare tool). Vacuum pump Provided to prevent the back flow of oil. This adapter enables you to use New adapter vacuum pumps. Electronic scale for It is difficult to measure R40A with a charging cylinder because the New refrigerant charging refrigerant bubbles due to high pressure and high-speed vaporization : t Substitutable for R40A : Substitutable for R40A 4

5 2.Refrigerant piping Specifications Use the refrigerant pipes that meet the following specifications. Pipe Outside diameter mm Wall thickness Insulation material For liquid For gas mm 0.8 mm 0.8 mm.0 mm Heat resisting foam plastic Specific gravity Thickness 8 mm Use a copper pipe or a copper-alloy seamless pipe with a thickness of 0.8 mm (6.35, 9.52, 2.7),.0 mm (5.88). Never use any pipe with a thickness less than 0.8 mm (6.35, 9.52, 2.7),.0 mm (5.88), as the pressure resistance is insufficient. 2 Flaring work and flare nut Flaring work for R40A pipe differs from that for R22 pipe. For details of flaring work, refer to Installation manual FLARING WORK. Pipe diameter mm Dimension of flare nut R40A R Refrigerant oil Apply the special refrigeration oil (accessories: packed with indoor unit) to the flare and the union seat surfaces. 4.Air purge Do not discharge the refrigerant into the atmosphere. Take care not to discharge refrigerant into the atmosphere during installation, reinstallation, or repairs to the refrigerant circuit. Use the vacuum pump for air purging for the purpose of environmental protection. 5.Additional charge For additional charging, charge the refrigerant from liquid phase of the gas cylinder. If the refrigerant is charged from the gas phase, composition change may occur in the refrigerant inside the cylinder and the outdoor unit. In this case, ability of the refrigerating cycle decreases or normal operation can be impossible. However, charging the liquid refrigerant all at once may cause the compressor to be locked. Thus, charge the refrigerant slowly. Union Stop valve Indoor unit Refrigerant gas cylinder operating valve Liquid pipe Gas pipe Service port Outdoor unit Gauge manifold valve (for R40A) Charge hose (for R40A) Refrigerant gas cylinder for R40A with siphon Refrigerant (liquid) Electronic scale for refrigerant charging 5

6 2 PART NAMES AND FUNCTIONS OUTDOOR UNIT MUH-A8WV - E MUH-A24WV - E MUH-A30WV - E Air inlet (back and side) Air inlet (back and side) Piping Drainage hose Air outlet Air outlet Drain outlet ACCESSORIES Outdoor unit 2 Drain socket Drain cap {33 Drain cap {6 MUH-A8WV- E 2 MUH-A24WV- E MUH-A30WV- E 2 3 SPECIFICATION Outdoor model Function Power supply Capacity Dehumidification Air flow(high) Power outlet Running current Power input Power factor Starting current Compressor motor current Fan motor current A Coefficient of performance(c.o.p) Capacity Electrical data Compressor Fan motor Special remarks Model Output Winding resistance(at 20:) Model Winding resistance(at 20:) Dimensions WOHOD Weight Sound level(high) Fan speed(high) Fan speed regulator Refrigerant filling capacity(r40a) Refrigerating oil (Model) Thermistor RT6(at 0:) kw r/h K /h A A W % A A W " " mm kg db rpm kg cc k" Cooling , MUH-A8WV - E Single phase 230V, 50Hz 2, RN96VHSHT,300 C-R.80 C-S 3.00 RA6V50-OG WHT-BLK 6 BLK-RED 850o605o (NEO22) Heating , NOTE: Test conditions are based on JIS C 962. Cooling : Indoor DB27 C WB9 C Heating : Indoor DB20 C WB 5.5 C Outdoor DB35 C WB(24 C) Outdoor DB 7 C WB 6 C Indoor-Outdoor piping length : 5m Cooling , MUH-A24WV - E Single phase 230V, 50Hz 2, NN29VBAHT,900 C-R 0.80 C-S.64 RA6V85-AB WHT-BLK 63 BLK-YLW 30 YLW-RED o850o ,200 (NEO22) 33.8 Heating ,420 98

7 Capacity Electrical data Outdoor model Function Power supply Capacity Dehumidification Air flow(high/low w) Power outlet Running current Power input Power factor Starting current Compressor motor current Fan motor current Coefficient of performance(c.o.p) Compressor Fan motor Special remarks Model Output Winding resistance(at 20:) Model Winding resistance(at 20:) Dimensions WOHOD Weight Sound level(high/low w) Fan speed(high/low w) Fan speed regulator Refrigerant filling capacity(r40a) Refrigerating oil (Model) Thermistor RT6(at 0:) Thermistor RT62(at 25:) Thermistor RT63(at 0:) kw R/h K /h A A W % A A A W " " mm kg db rpm kg cc k" k" k" MUH-A30WV - E Cooling Single phase 230V, 50Hz ,940/,470w , NN37VAAHT 2,500 C-R 0.64 C-S.63 RA6V75-AB WHT-BLK 62.8 BLK-YLW 55.9 YLW-RED o850o w 55/53 805/435 w ,300 (NEO 22) NOTE: Test conditions are based on JIS C 962. Cooling : Indoor DB27 C WB9 C Heating : Indoor DB20 C WB 5.5 C Outdoor DB35 C WB(24 C) Outdoor DB 7 C WB 6 C Indoor-Outdoor piping length : 5m w Reference value Heating 9.4 2,940/,470w 5.9 3,

8 4 NOISE CRITERIA CURVES MUH-A8WV- E MUH-A24WV- E FAN SPEED SPL(dB(A)) LINE FAN SPEED SPL(dB(A)) LINE High 52 High 53 OCTAVE BAND SOUND PRESSURE LEVEL, db re MICRO BAR Test conditions, Cooling : Dry-bulb temperature 35: Wet-bulb temperature 24: Heating : Dry-bulb temperature 7: Wet-bulb temperature 6: APPROXIMATE THRESHOLD OF HEARING FOR CONTINUOUS NOISE MUH-A30WV- E BAND CENTER FREQUENCIES, Hz NC-70 NC-60 NC-50 NC-40 NC-30 NC-20 OCTAVE BAND SOUND PRESSURE LEVEL, db re MICRO BAR Test conditions, Cooling : Dry-bulb temperature 35: Wet-bulb temperature 24: Heating : Dry-bulb temperature 7: Wet-bulb temperature 6: APPROXIMATE THRESHOLD OF HEARING FOR CONTINUOUS NOISE BAND CENTER FREQUENCIES, Hz NC-70 NC-60 NC-50 NC-40 NC-30 NC-20 FAN SPEED SPL(dB(A)) LINE High 55 OUTDOORUNIT OCTAVE BAND SOUND PRESSURE LEVEL, db re MICRO BAR Test conditions, Cooling : Dry-bulb temperature 35: Wet-bulb temperature 24: Heating : Dry-bulb temperature 7: Wet-bulb temperature 6: APPROXIMATE THRESHOLD OF HEARING FOR CONTINUOUS NOISE BAND CENTER FREQUENCIES, Hz NC-70 NC-60 NC-50 NC-40 NC-30 NC-20 m MICROPHONE 8

9 5 OUTLINES AND DIMENSIONS MUH-A8WV- E OUTDOOR UNIT Drainage hole [ Air in 20 00mm or more 00mm or more 00mm or more Unit: mm 248 Air in Drainage 3holes [33 Air out mm or more Service panel 350mm or more Liquid refrigerant pipe joint Refregerant pipe (flared) [ Gas refregerant pipe joint Refregerant pipe (flared) [2.7 MUH-A24WV- E MUH-A30WV- E OUTDOOR UNIT mm or more Open as a rule 500mm or more if the front and both sides are open 00mm or more 200mm or more if there are obstacles to both sides Open as a rule 500mm or more if the back, both sides and top are open 350mm or more Service panel 850 Liquid refrigerant pipe joint Refrigerant pipe (flared) [6.35 (MUH-A24WV) [9.52 (MUH-A30WV) Gas refrigerant pipe joint Refrigerant pipe (flared) [5.88 9

10 6 WIRING DIAGRAM MUH-A8WV - E OUTDOOR UNIT POWER SUPPLY ~ /N 230V 50Hz MODEL WIRING DIAGRAM TB2 3 TO INDOOR UNIT N CONNECTING 2V CIRCUIT BREAKER PE TB L N GRN/YLW RED BLK BRN BRN BLU DSAR BLU RT6 2 3 CN730 F6 TAB20 CN66 4 T6 52C 2S4 CN72 SR62 NR6 SR6 C65 3 DEICER P.C.BOARD C C WHT RED MC S R BLK RED ORN MF WHT BLK CN7 WHT BLK 2 RED 3 SYMBOL C C65 DSAR F6 MC NAME COMPRESSOR CAPACITOR OUTDOOR FAN CAPACITOR SURGE ABSORBER SYMBOL MF NR6 RT6 NAME OUTDOOR FAN MOTOR (INNER PROTECTOR) VARISTOR DEFROST THERMISTOR SYMBOL TB,TB2 2S4 52C FUSE (2A) SR6,SR62 SOLID STATE RELAY COMPRESOR (INNER PROTECTOR) T6 TRANSFORMER NOTES:.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 below indicate. : Terminal block : Connector NAME TERMINAL BLOCK R.V. COIL COMPRESSOR CONTACTOR VG79B553H0 MUH-A24WV - E OUTDOOR UNIT CIRCUIT BREAKER L TB POWER SUPPLY ~ /N 230V 50Hz TO INDOOR UNIT CONNECTING 2V N 3 N PE GRN/YLW TB2 BRN DSAR BLU MODEL WIRING DIAGRAM BLU BRN BLU BRN 3 RT6 CN66 X62 DEICER P.C. BOARD 52C 4 X52 A SR6 T6 WHT 52C YLW BLK 6 5 YLW BLK WHT WHT ORN RED 4 2 RED ORN C2 CN7CN72 X COM NO X52 TAB52 CN NR6 F6 3 A2 MF C COM RED BLK 0 NO S C MC R NOTES:.Use copper conductors only (For field wiring). 2.Since the indoor and outdoor unit connecting wires have polarity, connect them according to the numbers (3,N). 3.Symbols below indicate. : Terminal block, : Connector BLU 2S4 RED BLU SYMBOL C C2 DSAR F6 MC MF NR6 RT6 SR6 TB TB2 T6 X52 X62 2S4 52C NAME COMPRESSOR CAPACITOR OUTDOOR FAN CAPACITOR SURGE ABSORBER FUSE (3.5A) COMPRESSOR (INNER PROTECTOR) OUTDOOR FAN MOTOR (INNER PROTECTOR) VARISTOR DEFROST THERMISTOR SOLID STATE RELAY TERMINAL BLOCK TERMINAL BLOCK TRANSFORMER CONTACTOR R. V. COIL RELAY R. V. COIL COMPRESSOR CONTACTOR SG79J883H0

11 MUH-A30WV - E OUTDOOR UNIT CIRCUIT BREAKER TB L POWER SUPPLY ~ /N 230V 50Hz TO INDOOR UNIT CONNECTING 2V MODEL WIRING DIAGRAM N 3 N PE GRN/YLW TB2 BRN DSAR BLU BLU WHT RT6RT62 RT63 LEV CN66 X62 52C CZ 2 X52 DEICER PC BOARD BRN BLU BRN CN662 WHT 6 CN724 A SR62 SR6 T6 WHT 52C YLW BLK 6 5 YLW BLK WHT WHT ORN RED 4 RED ORN C2 CN7 CN72 X COM NO X52 TAB52 CN NR6 F6 3 A2 MF C 2 COM NO RED BLK C S MC R BLU 2S4 RED BLU SYMBOL NAME SYMBOL NAME SYMBOL NAME CZ C C2 DSAR F6 LEV MC CZ SURGE ABSRBER COMPRESSOR CAPACITOR OUTDOOR FAN CAPACITOR SURGE ABSORBER FUSE(3.5A) EXPANSION VALVE COIL COMPRESSOR (INNER PROTECTOR) MF NR6 RT6 RT62 RT63 SR6 SR62 OUTDOOR FAN MOTOR (INNER PROTECTOR) VARISTOR DEFROST THERMISTOR DISCHARGE TEMPERATURE THERMISTOR AMBIENT TEMPERATURE THERMISTOR SOLID STATE RELAY SOLID STATE RELAY TB TB2 T6 X52 X62 2S4 52C TERMINAL BLOCK TERMINAL BLOCK TRANSFORMER CONTACTOR R.V. COIL RELAY R.V. COIL COMPRESSOR CONTACTOR NOTE. Use copper conductors only (For field wiring). 2. Since the indoor and outdoor unit connecting wires have polarity, connect them according to the numbers (3,N). 3. Symbols below indicate. /: Terminal block, : Connector SG79J882H0

12 7 REFRIGERANT SYSTEM DIAGRAM MUH-A8WV - E OUTDOOR UNIT Refrigerant pipe [2.7 (with heat insulator) 4- way valve Unit:mm Flared connection Stop valve (with service port) Oil separator #00 Defrost thermistor RT6 Outdoor heat exchanger Capillary tube [2.5o[0.6o,000 Compressor Flared connection Refrigerant pipe[6.35 (with heat insulator) Stop valve Receiver Strainer #00 Capillary tube [3.0o[.6o450 Capillary tube [3.0o[.6o750 (2 pcs) R.V. coil Heating ON Cooling OFF Capillary tube Check valve [3.0o[.6o300 Refrigerant flow in cooling Refrigerant flow in heating MUH-A24WV - E OUTDOOR UNIT Refrigerant pipe [5.88 (with heat insulator) 4- way valve Flared connection Stop valve (with service port) Muffler Muffler #00 Outdoor heat exchanger Compressor Defrost thermistor RT6 Flared connection Capillary tube [3.0X[2.0X550 Receiver Refrigerant pipe [6.35 (with heat insulator) Stop valve Strainer #00 Capillary tube [3.0X[2.0X650 R.V. coil Heating ON Check valve Cooling OFF Refrigerant flow in cooling Refrigerant flow in heating 2

13 MUH-A30WV - E OUTDOOR UNIT Refrigerant pipe [5.88 (with heat insulator) 4-way valve Muffler #00 Unit:mm Flared connection Stop valve (with service port) Discharge temperature thermistor RT62 Defrost thermistor RT6 Outdoor heat exchanger Muffler Compressor Ambient temperature thermistor RT63 Flared connection Refrigerant pipe [9.52 (with heat insulator) Strainer Receiver #00 Stop valve Capillary tube [3.6 [ LEV Strainer #00 R.V. coil heating ON cooling OFF Refrigerant flow in cooling Refrigerant flow in heating MAX. REFRIGERANT PIPING LENGTH Model Refrigerant piping Max. length : m A Piping size O.D : mm Gas Liquid Length of connecting pipe : m Indoor unit Outdoor unit MUH-A8WV - E MUH-A24WV - E MUH-A30WV - E Gas 0.43 Liquid 0.5 Gas 0 Liquid 0 MAX. HEIGHT DIFFERENCE Indoor unit wmax. Height difference: 0m(MSH-A8/A24WV)/ 5m(MSH-A30WV) Refrigerant Piping Max. Length A Outdoor unit w Height difference should be within 0m(MSH-A8/A24WV)/ 5m(MSH-A30WV) regardless of which unit, indoor or outdoor position is high. 3

14 ADDITIONAL REFRIGERANT CHARGE(R40A : g) Model Outdoor unit precharged 7m Refrigerant piping length (one way) 0m 5m 20m 25m MUH-A8WV - E, Calculation : Xg=20g/m (Refrigerant piping length (m) 7) Model Outdoor unit precharged 7m Refrigerant piping length (one way) 0m 5m 20m 25m MUH-A24WV - E 2, Calculation : Xg=20g/m (Refrigerant piping length (m) 7) Model Outdoor unit precharged 7m 0m Refrigerant piping length (one way) 5m 20m 25m 30m MUH-A30WV - E 2, ,265 Calculation : Xg=55g/mo(Refrigerant piping length(m)-7) 4

15 8 PERFORMANCE CURVES MUH-A8WV - E MUH-A24WV - E MUH-A30WV - E The standard data contained in these specifications apply only to the operation of the air conditioner under normal conditions, since operating conditions vary according to the areas where these units are installed. The following information has been provided to clarify the operating characteristics of the air conditioner under the conditions indicated by the performance curve. () GUARANTEED VOLTAGE 98 ~ 264V, 50Hz (2) AIR FLOW Air flow should be set at MAX. (3) MAIN READINGS () Indoor intake air wet-bulb temperature : CWB (2) Indoor outlet air wet-bulb temperature : CWB (3) Outdoor intake air dry-bulb temperature : CDB (4) Total input: W (5) Indoor intake air dry-bulb temperature : CDB (6) Outdoor intake air wet-bulb temperature : CWB (7) Total input : W Indoor air wet/dry-bulb temperature difference on the left side of the chart on this page and next page shows the difference between the indoor intake air wet/dry-bulb temperature and the indoor outlet air wet/dry-bulb temperature for your reference at service. How to measure the indoor air wet-bulb/dry-bulb temperature difference. 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. 2. 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. 3. Check that the air filter is cleaned. 4. 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 5 minutes, measure temperature and take an average temperature minutes later, measure temperature again and check that the temperature does not change. INDOOR UNIT OUTDOOR UNIT } } Cooling Heating Wet-and dry-bulb thermometers Wet-and dry-bulb thermometers MSH-A8WV - E MUH-A8WV - E MSH-A24WV - E MUH-A24WV - E MSH-A30WV - E MUH-A30WV - E 5

16 MSH-A8WV - E MUH-A8WV - E MSH-A24WV - E MUH-A24WV - E MSH-A30WV - E MUH-A30WV - E NOTE:The above curves are for the heating operation without any frost. OUTDOOR LOW PRESSURE AND OUTDOOR UNIT CURRENT COOL operation Both indoor and outdoor unit are under the same temperature/humidity condition. Dry-bulb temperature Relative humidity(%) Air flow should be set at MAX. 3 The unit of pressure has been changed to MPa on the international system of units(si unit system). The conversion factor is : (MPa [Gauge]) =0.2(kgf/f [Gauge]) (kgf/f[gauge])(mpa[gauge]) Outdoor low pressure MUH-A8WV - E 230V MUH-A8WV - E 230V (:) (%) 70(%) Ambient temperature( C) Ambient temperature( C) Ambient humidity(%) Ambient humidity(%) Outdoor unit current (A) 35(:) (kgf/f[gauge])(mpa[gauge]). Outdoor low pressure MUH-A24WV - E 230V Outdoor unit current (A) 0 9 MUH-A24WV - E 230V (%) 35(:) Ambient temperature( C) Ambient humidity(%) 8 Ambient temperature( C) Ambient humidity(%) 6

17 (kgf/f[gauge])(mpa[gauge]) Outdoor low pressure MUH-A30WV - E 230V Outdoor unit current(a) MUH-A30WV - E 230V (:) (%) Ambient temperature( C) Ambient humidity(%) HEAT operation Condition indoor:dry bulb temperature 20.0 C Wet bulb temperature 4.5 C (:) (%) Ambient temperature( C) Ambient humidity(%) Outdoor:Dry bulb temperature 7,5,20 C Wet bulb temperature 6,2,4.5 C 0 MUH-A8WV - E 4 MUH-A24WV - E Outdoor unit current (A) V Outdoor unit current (A) V (:) Ambient temperature( C) Ambient temperature( C) 20 MUH-A30WV - E 230V Outdoor unit current(a) (:) Ambient temperature( C) 7

18 PERFORMANCE DATA COOL operation MSH-A8WV - E : MUH-A8WV - E (230V) CAPACITY : 5.0(KW) SHF : 0.65 INPUT : 780(W) OUTDOOR DB(:) INDOOR DB(:) INDOOR WB(:) Q SHC SHF INPUT Q SHC SHF INPUT Q SHC SHF INPUT Q 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 8

19 PERFORMANCE DATA COOL operation MSH-A8WV - E : MUH-A8WV - E (230V) CAPACITY : 5.0(KW) SHF : 0.65 INPUT : 780(W) OUTDOOR DB(:) INDOOR DB(:) INDOOR WB(:) Q SHC SHF INPUT Q SHC SHF INPUT Q 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 9

20 PERFORMANCE DATA COOL operation MSH-A24WV - E : MUH-A24WV - E (230V) CAPACITY : 6.3(KW) SHF : 0.64 INPUT : 240(W) OUTDOOR DB(:) INDOOR DB(:) INDOOR WB(:) Q SHC SHF INPUT Q SHC SHF INPUT Q SHC SHF INPUT Q 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 20

21 PERFORMANCE DATA COOL operation MSH-A24WV - E : MUH-A24WV - E (230V) CAPACITY : 6.3(KW) SHF : 0.64 INPUT : 240(W) OUTDOOR DB(:) INDOOR DB(:) INDOOR WB(:) Q SHC SHF INPUT Q SHC SHF INPUT Q 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 2

22 PERFORMANCE DATA COOL operation MSH-A30WV - E : MUH-A30WV - E (230V) CAPACITY : 8.5(KW) SHF : 0.62 INPUT : 3260(W) OUTDOOR DB(:) INDOOR DB(:) INDOOR WB(:) Q SHC SHF INPUT Q SHC SHF INPUT Q SHC SHF INPUT Q 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 22

23 PERFORMANCE DATA COOL operation MSH-A30WV - E : MUH-A30WV - E (230V) CAPACITY : 8.5(KW) SHF : 0.62 INPUT : 3260(W) OUTDOOR DB(:) INDOOR DB(:) INDOOR WB(:) Q SHC SHF INPUT Q SHC SHF INPUT Q 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 23

24 PERFORMANCE DATA HEAT operation MSH-A8WV - E : MUH-A8WV - E (230V) CAPACITY : 5.2(KW) INPUT : 60(W) OUTDOOR WB(:) INDOOR DB(:) Q INPUT Q INPUT Q INPUT Q INPUT Q INPUT Q INPUT Q INPUT NOTE Q :Total capacity (kw) INPUT:Total power input (W) DB : Dry-bulb temperature MSH-A24WV - E : MUH-A24WV - E (230V) CAPACITY : 7.2(KW) INPUT : 2480(W) OUTDOOR WB(:) INDOOR DB(:) Q INPUT Q INPUT Q INPUT Q INPUT Q INPUT Q INPUT Q INPUT NOTE Q :Total capacity (kw) INPUT:Total power input (W) DB : Dry-bulb temperature MSH-A30WV - E : MUH-A30WV - E (230V) CAPACITY : 9.4(KW) INPUT : 3430(W) OUTDOOR WB(:) INDOOR DB(:) Q INPUT Q INPUT Q INPUT Q INPUT Q INPUT Q INPUT Q INPUT NOTE Q :Total capacity (kw) INPUT:Total power input (W) DB : Dry-bulb temperature

25 9 MICROPROCESSOR CONTROL MUH-A8WV - E MUH-A24WV - E MUH-A30WV - E 9-. I FEEL CONTROL ( ) OPERATION 9--. COOL mode of I FEEL CONTROL. Outdoor fan speed control <MUH-A30WV> Outdoor fan speed is controlled according to the temperature of ambient temperature thermistor RT63. Outdoor fan Low operation : When the outside temperature decreases to 20 C or less. Until the outside temperature goes to 22 C. Outdoor fan High operation : Until the outside temperature decreases to 20 C or less. When the outside temperature goes to 22 C. 2. Discharge temperature protection <MUH-A30WV> The compressor is controlled by the temperature of discharge temperature thermistor RT62 for excess rise protection of compressor discharge pressure. Compressor When the temperature of discharge temperature thermistor RT62 goes to 20: or more, the compressor is turned OFF. After 3 minutes since the compressor has been turned OFF, if the temperature of discharge temperature thermistor RT62 becomes 00: or less, the compressor is turned ON DRY mode of I FEEL CONTROL. Outdoor fan speed control <MUH-A30WV> Outdoor fan speed control is as same as one of COOL mode of I FEEL CONTROL HEAT mode of I FEEL CONTROL Ambient temperature Outdoor fan speed thermistor RT63 temperature 20: 22: NOTE. : If the temperature of RT63 reads from 20: to 22: at the air conditioner starting outdoor fan speed is High. NOTE2. : When indoor fan speed is Low except HEAT operation mode and the outside temperature is 30: or less, the outdoor fan operates at Low. Outdoor fan Low operation is cancelled according to the following conditions( or 2): When the operation is not changed and the outside temperature goes to 33: or more. 2 When the operation is changed. (Change to HEAT operation mode / Change of the indoor fan speed). Outdoor fan speed control <MUH-A30WV> Outdoor fan speed is controlled according to the temperature of ambient temperature thermistor RT63. Outdoor fan Low operation : Until the outside temperature decreases to 3 C. When the outside temperature goes to 8 C or more. Outdoor fan High operation :When the outside temperature decreases to 3 C or less. Until the outside temperature goes to 8 C. 2. High pressure protection <MUH-A8/A24WV> During heating operation, the outdoor fan motor is controlled by the temperature of indoor coil thermistor RT2 for excess rise protection of compressor discharge pressure. (MUH-A8WV)Outdoor fan OFF : 52 C Outdoor fan ON : 48 C (MUH-A24WV)Outdoor fan OFF : 58 C Outdoor fan ON : 55 C High pressure protection chart Example Indoor coil thermistor RT2 temperature (MUH-A8WV) 52 C (MUH-A24WV) 58 C (MUH-A8WV) 48 C (MUH-A24WV) 55 C Ambient temperature thermistor RT63 temperature High pressure protection Released (MUH-A8WV) 48: 52: (MUH-A24WV) 55: 58: Outdoor fan speed Outdoor fan OFF ON 3: 8: High Low High Low Outdoor fan motor turn OFF Outdoor fan motor turn ON Outdoor fan motor ON OFF ON OFF 25

26 NOTE : During high pressure protection and for 4 minutes and 5 seconds after high pressure protection, defrosting of outdoor heat exchanger is not detected by the defrost thermistor RT6. <MUH-A30WV> During heating operation, the outdoor fan and the compressor are controlled by the temperature of indoor coil thermistor RT2 for excess rise protection of compressor discharge pressure. Outdoor fan When the temperature of indoor coil thermistor RT2 goes to 55: or more, the outdoor fan is turned OFF. When the temperature of indoor coil thermistor RT2 becomes to 52: or less, the outdoor fan is turned ON. Compressor When the temperature of indoor coil thermistor RT2 goes to 75: or more, the compressor is turned OFF. 3 minutes after the compressor is turned OFF and if the temperature of indoor coil thermistor RT2 becomes 75: or less, the compressor is turned ON. NOTE : During the high pressure protection and for 0 seconds after high pressure protection, defrosting of outdoor heat exchanger is not detected by the defrost thermistor RT6. 3. Discharge temperature protection <MUH-A30WV> Discharge temperature protection is as same as during COOL mode of I FEEL CONTROL. 4. Defrosting Defrosting of outdoor heat exchanger is controlled by deicer P.C. board, with detection by the defrost thermistor RT6. () Starting conditions of defrost When all conditions of a) ~ c) are satisfied, the defrosting operation starts. a) Under the heat operation, the compressor cumulative operation time exceeds 40 minutes without the defrosting operation working. b) The defrost thermistor RT6 reads -3 C or less. c) After releasing the high pressure protection 4 minutes and 5 seconds(muh-a8/a24wv) / 0 seconds(muh-a30wv) have elapsed. (2) Releasing conditions of defrost When the condition d) or e) is satisfied, the defrosting operation stops. d) The defrost thermistor RT6 reads 3 C(MUH-A8/A24WV)/ 3 C(MUH-A30WV) or more. e) The defrosting time exceeds 0 minutes. (3) Defrosting time chart Defrost thermistor RT6 3: or more(muh-a30wv) 3: or more(muh-a8/a24wv) -3: or less Outdoor 52C contactor(compressor) ON OFF X62 (R.V. coil) ON OFF 30 sec. 5 sec. 30 sec. 5 sec. SR6 Outdoor fan ON OFF Defrost counter ON OFF Max 0 min. Indoor fan Indoor vane ON Very Low OFF Horizontal Set position NOTE NOTE: When the indoor coil thermistor RT2 reads above 8 C, indoor fan operates at Very Low for 30 seconds. When the indoor coil thermistor RT2 reads 8 C or less, the indoor fan stops. 26

27 5. R.V. coil control Heating ON Cooling OFF Dry OFF NOTE: The 4-way valve reverses for 5 seconds right before start-up of the compressor. (COOL / DRY) (HEAT) 5 sec. 5 sec. Compressor R.V. coil Outdoor fan ON OFF ON OFF ON OFF ON OFF ON OFF ON OFF 9-2. LEV control <MUH-A30WV> LEV (Expansion valve) is controlled by Thermostat ON commands given from the unit. Basic specification General operation Controlled range Drive speed Opening set Stop of indoor unit Remote controller ON Power ON (Breaker ON) Approximate for 2 minutes since compressor has started. From approximate 2 minutes to approximate 3 minutes (for minutes) since compressor has started. After 3 minutes passed since compressor has started. At thermostat OFF At thermostat ON At remote controller OFF Minimum : 54 pulse, Maximum : 500 pulse 30 ~ 90 pulse / second The setting is always in opening direction. (To close the LEV, it is closed to the pulse smaller than the one which is set finally. Then the LEV is opened to the final setting pulse.) Opening in stop : 50 pulse LEV opening is set to becomes 500 pulse after 3 minutes passed. LEV positioning (LEV is closed completely at once) LEV is positioned. However, afterwards, LEV is not positioned at the first remote controller ON. Opening is set by the initial opening. (Initial opening is set according to each operation modes and outer temperature conditions.) Opening is set by standard opening. (Standard opening is set according to each operation modes and outer temperature conditions.) LEV opening is corrected to be once every 2 minutes so that discharge temperature becomes the target discharge temperature. (When the discharge temperature is lower than target one : LEV is corrected in closed direction, when the discharge temperature is higher than target one : LEV is corrected in opening direction.) Opening in stop : 50 pulse LEV is set to the initial opening after about 3 minutes passed. Same as the starting of compressor operation Opening in stop : 50 pulse LEV is set so that the opening is opened completely at the speed of 4 pulse every 5 seconds in opening after about 3 minutes passed. 27

28 () LEV opening correction by discharge temperature The LEV opening is corrected according to the temperature difference between target discharge temperature (Tb) and actual discharge temperature (Ta). The LEV correction is used properly for two kinds according to the LEV opening status at operation off. Rank Ta (:) more than Tb+0 Tb+5 to Tb+0 Tb+2 to Tb+5 Tb-2 to Tb+2 Tb-5 to Tb-2 Tb-0 to Tb-5 less than Tb-0 2 When the temperature difference RT between indoor coil thermistor (main) RT2 and indoor coil thermistor (sub) RT3 in the indoor unit is 2: or more for a fixed time at cool or dry operation, the target discharge temperature is changed. After the temperature is changed, when temperature difference RT is 3: or more, the target temperature is changed again. The LEV opening is controlled based on the changed target discharge temperature and the temperature difference RT. Ta (:) more than Tb+0 Tb+5 to Tb+0 Tb+2 to Tb+5 Tb-2 to Tb+2 Tb-5 to Tb-2 Tb-0 to Tb-5 less than Tb-0 00 pulse or less Cooling / Heating NOTE : Discharge temperature : Ta, Target discharge temperature : Tb less than 2: NOTE : Discharge temperature : Ta, Target discharge temperature : Tb Opening immediately before having stopped last time RT 2: or more and less than 3: pulse or more Cooling / Heating 3: or more The target discharge temperature (Tb) is set according to the operation mode or the unit status as follows Operation mode HEAT COOL (rmal) COOL ( RT is less than 2:, or RT is 2:or more and less than 3:.) COOL ( RT is 3 :or more.) Tb (:) NOTE : Target discharge temperature : Tb NOTE : When the discharge temperature (Ta) is 50: or less on the cool operation, or is 49: or less on heat operation, LEV opening is set in 54 pulse. When this state continues for 20 minutes, the compressor is stopped and restarts in 3 minutes. When the compressor is stopped, the indoor unit indicates the abnormality of refrigerant system and stops. (OPERATION INDICATOR lamp is 0-time flashing on and off.) 28

29 (2) LEV time chart Open Opening Power ON completely Remote controller Operation ON Standard opening LEV opening Close 0 Positioning Initial opening Thermostat OFF Operation Standard opening Thermostat ON Initial opening Opening in stop Remote controller OFF Opening in stop Opening completely Remote controller ON Positioning Standard opening Initial opening NOTE : Opening increases and decreases to be in the target discharge temperature during operation. SERVICE FUNCTIONS Operation Time MUH-A8WV - E MUH-A24WV - E MUH-A30WV - E 0-. COMPULSORY DEFROSTING MODE FOR SERVICE By short circuit of the connector JPDS and JPSG(MUH-A8WV)/ JPG and R87(MUH-A24/A30WV) on the outdoor deicer P.C. board, defrosting mode can be accomplished regardless of the defrost interval restriction. (Refer to page 37 or 38.) Defrost thermistor RT6 must read below -3 C CHANGE IN DEFROST SETTING <JRF> When the JRF wire of the deicer P.C. board is cut, the defrost interval time will be changed. <JRG> When the JRG wire of the deicer P.C. board is cut, the defrost temperature will be changed. (Refer to page 37 or 38.) Model MUH-A8WV - MUH-A24WV - MUH-A30WV - E E E Jumper wire JRF JRG Change point Defrost interval time changes from 40 minutes to 5 minutes. Defrost start temperature changes from -3: to 0:. (MUH-A8WV) Defrost start temperature does not change.(-3.0:)(muh-a24/a30wv) Defrost finish temperature changes from 3: to 0:.(MUH-A8WV) Defrost finish temperature changes from 3: to 5:.(MUH-A24WV) Defrost finish temperature changes from 3: to 5:.(MUH-A30WV) TROUBLESHOOTING MUH-A8WV - E MUH-A24WV - E MUH-A30WV - E -. Cautions on troubleshooting. Before troubleshooting, check the following: () Check the power supply voltage. (2) Check the indoor/outdoor connecting wire for mis-wiring. 2. Take care the following during servicing. () 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 / 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 electronic control P.C. board, hold the edge of the board with care NOT to apply stress on the components. (4) When connecting or disconnecting the connectors, hold the housing of the connector. DO NOT pull the lead wires. Lead wiring Housing point 3. Troubleshooting procedure () First, 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 abnormality indication is flashing on and off before starting service work. (2) Before servicing check that the connector and terminal are connected properly. (3) If the electronic control P.C. board is supposed to be defective, check the copper foil pattern for disconnection and the components for bursting and discolouration. (4) When troubleshooting, refer to the flow chart on page

30 Start Indoor unit operates. Outdoor unit doesn't operate. Indoor unit operates. Outdoor unit doesn't operate normally. Indoor unit doesn't receive the signal from remote controller. OPERATION INDICATOR lamp on the indoor unit is flashing on and off. Outdoor unit operates in only Test Run operation. Outdoor unit doesn't operate even in Test Run operation. Outdoor unit doesn't stop even if indoor unit stops. Unit doesn't operate normal operation in COOL or HEAT mode. Indoor unit operates, when the EMERGENCY OPERATION switch is pressed. Indoor unit doesn't operate, when the EMERGENCY OPERATION switch is pressed. Check room temperature thermistor. Refer to "Test point diagram and voltage". Refer to A "Check of outdoor unit" on page 32 or 33. Refer to B "Check of outdoor unit" on page 34. Refer to C "Check of R.V. coil" on page 34 or 35. Refer to "Check of remote controller and receiver P.C. board".. Check indoor / outdoor connecting wire. 2. Refer to "Check of indoor electronic control P.C. board". Flash on and off at 0.5- second intervals Cause: Indoor/ Outdoor unit Mis-wiring 2-time flash Cause: Indoor unit Trouble of room temperature/ indoor coil thermistor 3-time flash Cause: Indoor unit Trouble of indoor fan motor 4-time flash Cause: Indoor unit Trouble of indoor unit control system 6-time flash Cause: Outdoor unit Trouble of thermistor in outdoor unit 7-time flash Cause: Outdoor unit Trouble of outdoor control system 0-time flash Cause: Outdoor unit MUH-A30WV Trouble of low discharge temperature protection Refer to D "How to check mis-wiring (When outdoor unit doesn't work)" on page 35. Check room temperature thermistor and indoor coil thermistor. Refer to "Test point diagram and voltage". Refer to "Check of indoor fan motor". Replace the indoor electronic control P.C. board. Refer to F "Check of outdoor thermistor" on page 36. Replace the deicer P.C. board. MUH-A30WV Refer to E "Check of LEV" on page 36. As for indoor unit, refer to service manual OB32. 30

31 -2. Trouble criterion of main parts MUH-A8WV - E MUH-A24WV - E MUH-A30WV - E Part name Defrost thermistor (RT6) Discharge temperature thermistor(rt62) MUH-A30WV Ambient temperature thermistor(rt63) MUH-A30WV Check method and criterion Measure the resistance with a tester. (Part temperature 0 C ~ 40 C) rmal 5 k" ~ 60 k" Measure the resistance with a tester. Before measurement, hold the thermistor with your hands to warm it up. (Part temperature 0 C ~ 40 C) rmal 20 k" ~ 800k" Measure the resistance with a tester. (Part temperature 0 C ~ 40 C) rmal 5 k" ~ 60 k" Abnormal Open or short-circuit Abnormal Open or short-circuit Abnormal Open or short-circuit Figure Compressor (MC) INNER PROTECTOR 60i 5: OPEN 90i0: CLOSE Measure the resistance between the terminals with a tester. (Part temperature 0 C ~ 40 C) Terminal C R C S MUH-A8WV.59 " ~.95 " 2.65 " ~ 3.24 " rmal MUH-A24WV 0.7 " ~ 0.87 ".45 " ~.77 " MUH-A30WV 0.56 " ~ 0.7 ".43 " ~.76 " Abnormal Open or short-circuit S WHT C P ~ AUX MAIN RED R BLK MUH-A8WV MAIN AUX Outdoor fan motor(mf) MUH-A8/A24WV INNER PROTECTOR 45i 8: OPEN ( 88i5: CLOSE w ) MUH-A30WV INNER PROTECTOR 35i 5: OPEN ( 83i5: CLOSE w ) Measure the resistance between the terminals with a tester. (Part temperature 0 C ~ 40 C) Color of lead wire WHT BLK BLK RED BLK YLW YLW RED rmal MUH-A8WV MUH-A24WV MUH-A30WV 02 " ~ 26 " 55 " ~ 68 " 55.4 " ~ 67.7 " 97 " ~ 20 " 26 " ~ 33 " 49.3 " ~ 60.3 " 55 " ~ 68 " 22.9 " ~ 28.0 " Abnormal Open or short-circuit P BLK RED ORN WHT MUH-A24WV MAIN AUX. AUX.2 P C BLK YLW RED ORN WHT MUH-A30WV MAIN AUX.AUX.2 P R.V. coil(2s4) LEV(Expansion valve) MUH-A30WV w Reference value Measure the resistance between the terminals with a tester. (Part temperature 0 C ~ 40 C) rmal k" ~ k" Measure the resistance with a tester. (Part temperature : 0 C ~ 40 C) Color of lead wire rmal WHT RED RED ORN 4.0 " ~ 49.0 " YLW BRN BRN BLU Abnormal Open or short-circuit Abnormal Open or short-circuit WHT6 C BLK YLW REDORNWHT RED ORN4 YLW5 LEV BRN2 BLU3 P :INNER PROTECTOR 3

32 Compressor and/or outdoor fan motor doesn t operate. A Check of outdoor unit MUH-A8WV Operate the unit in COOL or HEAT mode by pressing the EMERGENCY OPERATION switch. 3-minute time delay works. Test run operation operates for 30 minutes. Compressor doesn't operate. Is there 5V DC between J205 + J0 on the deicer P.C. board? w Is there 230V AC between 3 on the compressor contactor (52C) and N on the outdoor terminal block (TB)? Check the compressor and compressor capacitor. Refer to page 3. Replace the deicer P.C. board. Is there 230V AC between 4 on the compressor contactor (52C) and TAB20 on the deicer P.C. board? w Replace the deicer P.C. board. Rectify the indoor and outdoor connecting wire. Is there 230V AC between L N on the outdoor terminal block (TB)? Rectify the connecting wire. Outdoor fan motor doesn't operate. Rectify the indoor and outdoor connecting wire. Is there 5V DC between J205 + J0 on the deicer P.C. board? w Is there 230V AC between 4 on the compressor contactor (52C) and TAB 20 on the deicer P.C. board? w Is there 230V AC between L N on the outdoor terminal block (TB)? Check the outdoor fan motor. Refer to page 3. Replace the deicer P.C. board. Rectify the connecting wire. w Refer to page

33 MUH-A24WV MUH-A30WV Turn ON the power supply. Is there 230V AC to between L-N on the outdoor terminal block? Check the outdoor power supply and connection of wiring. Compressor does not operate. Is there 5V DC between J0 + - J40 on the deicer P.C. board? w Is there 230V AC between CN730-3 on the deicer P.C. board? w Rectify the connecting wire. Operate the unit in COOL or HEAT mode by pressing the EMERGENCY OPERATION switch. Replace the deicer P.C. board. 3minutes after the power supply turns ON, is there 230V AC between A-A2 on the compressor contactor (52C)? Replace the deicer P.C. board. Is there 230V AC between 2/T on the compressor contactor(52c) and N on the outdoor terminal block? Is there 230V AC between /L on the compressor contactor(52c) and N on the outdoor terminal block? Rectify the connecting wire. Check the compressor. Refer to page 3. Replace the compressor contactor(52c). Outdoor fan motor does not operate. Is there 5V DC between J0 + - J40 on the deicer P.C. board? w Is there 230V AC CN730-3 on the deicer P.C. board? w Rectify the connecting wire. Operate the unit in COOL or HEAT mode by pressing the EMERGENCY OPERATION switch. Replace the deicer P.C. board. Is there 230V AC between CN7 2-3 (MUH-A24WV)/ CN7-3 or 2-3 (MUH-A30WV) on the deicer P.C. board? w Replace the deicer P.C. board. Check the outdoor fan motor. Refer to page 3. w Refer to page

34 Compressor and/or outdoor fan motor doesn t stop. B Check of outdoor unit MUH-A8WV Turn OFF the power supply. After minute, turn ON power supply again. Does compressor stop? OK Is there 230V AC between 3 on the compressor contactor (52C) and N on the outdoor terminal block (TB)? Replace the deicer P.C. board. Rectify the connecting wire. Does outdoor fan motor stop? Replace the deicer P.C. board. OK MUH-A24WV MUH-A30WV Turn OFF the power supply. 2 After 30 seconds, turn ON the power supply again. 3 Operate the unit in COOL or HEAT mode by pressing the EMERGENCY OPERATION switch. 4 Operate the unit for minute or more and stop it by pressing the EMERGENCY OPERATION switch again. After 30 seconds, does compressor stop? Ok Is there 230V AC between A-A2 on the compressor contactor (52C)? Replace the deicer P.C. board. Is there 230V AC between 2/T on the compressor contactor (52C) and N on the outdoor terminal block? Replace the compressor contactor(52c). Rectify the connecting wire. After 30 seconds, does outdoor fan motor stop? Replace the deicer P.C. board. Ok Unit operates HEAT mode even if it is set to COOL mode. C Check of R.V. coil w First, measure the resistance of R.V. coil to confirm it is disconnected or is not short-circuit. Disconnect the TAB52 on the deicer P.C. board. (MUH-A24/A30WV) Turn ON the power supply and operate the indoor unit in COOL mode by pressing the EMERGENCY OPERATION switch. After 3 minutes, does the unit operate in HEAT mode? Ok Is there 230V AC between CN72 2 (MUH-A8WV)/ CN72 3 (MUH-A24/A30WV) on the deicer P.C. board? Replace the deicer P.C. board. Replace the R.V. coil. 34

35 Unit operates COOL mode even if it is set to HEAT mode. C Check of R.V. coil w First, measure the resistance of R.V. coil to confirm it is disconnected or is not short-circuit. Disconnect the TAB52 on the deicer P.C. board. (MUH-A24/A30WV) Turn ON the power supply and operate the indoor unit in HEAT mode by pressing the EMERGENCY OPERATION switch. After 3 minutes, does the unit operate in COOL mode? OK Is there 230V AC between CN72 2 (MUH-A8WV)/ CN72 3 (MUH-A24/A30WV) on the deicer P.C. board? Replace the deicer P.C. board When OPERATION INDICATOR lamp flashes ON and OFF in every 0.5-second. Outdoor unit doesn t operate. Replace the R.V. coil. 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. (indoor/ outdoor unit) Press once EMERGENCY OPERATION switch. After 3 minutes, mis-wiring is indicated (0.5-second ON, 0.5-second OFF) on OPERATION INDICATOR lamp on indoor unit.w Make them sure. Is this mis-wiring, poor contact, or wire disconnection?. Turn OFF the power supply (indoor/ outdoor unit) and disconnect indoor/outdoor connecting wire on indoor side. 2. Short-circuit terminal block N-3 by lead wire. 3. Turn ON the power supply (indoor unit) and press once EMERGENCY OPERATION switch. Is there 20V DC between both ends of R32 on the indoor electronic control P.C. board? ( By tester, the stylus is between 0 ~ 20V. ) Replace the indoor electronic control P.C. board. Turn OFF the power supply. (indoor unit) Connect ON indoor/outdoor connecting wire. Turn ON the power supply. (outdoor unit) Is there 230V AC between L-N on the outdoor terminal block? Check the outdoor power supply and connection of wiring. Is there 5V DC between J J0 - (MUH-A8WV)/J0 + -J40 - (MUH-A24/A30 WV) on the deicer P.C. board?(refer to page 37 or 38.) During EMERGENCY OPERATION, is there 0V DC between both ends of R60on the deicer P.C. board? (Refer to page 37or 38.) (By tester, the stylus is between 5 ~0V) Replace the deicer P.C. board. Replace the deicer P.C. board. Make the wiring between CN730 on the deicer P.C. board and outdoor terminal block correct. (Refer to page 37 or 38.) As for indoor unit, refer to service manual OB32. 35

36 When OPERATION INDICATOR lamp flashes 0-time. Heating/ Cooling doesn't operate. E Check of LEV (Expansion valve) MUH-A30WV During pressing OPERATION SELECT button on remote controller, press RESET button. 2 First, release RESET button. (Confirm all displays of remote controller.) 3 Then release OPERATION SELECT button. During pressing OPERATION SELECT button on remote controller, press RESET button. 2 First, release RESET button. With remote controller set toward the indoor unit, press OPERATE/ STOP(ON/ OFF) button and confirm one beep tone. LEV operates in full-opening direction. C CLOCK AMPM AMPM (Confirm all displays of remote controller.) 3 Then release OPERATION SELECT button. Do you hear LEV "click, click "? Do you touch LEV and feel it vibrate? Ok Characteristics of LEV coil Is LEV coil properly fixed to the body? Does the resistance of LEV coil have the characterictics? Properly fix LEV coil to the body. Replace the deicer P.C. board. LEV (CN724) WHT RED RED ORN YLW BRN BRN BLU Resistance 4.0 " ~ 49.0 " Replace the LEV coil. NOTE : After check of LEV, do the undermentioned operations.. Turn OFF the power supply of the unit and turn ON again. 2. Press the RESET button on the remote controller. When OPERATION INDICATOR lamp flashes 6-time. Thermistors in the outdoor unit are abnormal. F Check of outdoor thermistor w Disconnect the connectors CN66 and/ or CN662 from the deicer P.C. board. (Check the characteristics of each thermistor.) Defrost thermistor(rt6) Measure resistance between CN 66 and 2. Turn OFF the power supply. <MUH-A30WV> Discharge temperature thermistor(rt62) Measure resistance between CN 662 and 2. Does the resistancs of thermistor have the characteristics on page 37 or 38? Connect CN66 and CN662. Turn ON the power supply and press the EMERGENCY OPERATION switch. Replace the deicer P.C. board. Does the unit operate 0 minutes or more? <MUH-A30WV> Ambient temperature thermistor(rt63) Replace the thermistor. Ok W. Measure resistance between CN and 4. W It is thought defective contact of the connector. 36

37 230V AC} MUH-A8WV - E Outdoor deicer P.C. board CN7 Outdoor fan motor 230V AC } CN72 R.V. coil 230V AC } Power supply input NR6 Varistor 5V DC J205 J (Refer to page 32 or 35.) } F6 Fuse 2A/250V + -- R60 5~0V DC CN66-2 Defrost thermistor RT6 (Refer to page 36.) } Defrost interval time short pin (JPDS, JPSG) (Refer to page 29.) } Jumper wire for change in defrost setting (JRF,JRG) (Refer to page 29.) 2V DC J204 J

38 Resistance(k") MUH-A24WV - E MUH-A30WV - E Outdoor deicer P.C. board Defrost thermistor (RT6) Ambient temperature thermistor (RT63) Resistance(k") Temperature(:) Discharge temperature thermistor(rt62) Temperature(:) CN66-2 Defrost thermistor (RT6) (Refer to page 36.) <MUH-A30WV> CN662-2 Discharge temperature thermistor (RT62) (Refer to page 36.) CN <MUH-A30WV> Ambient temperature thermistor (RT63) (Refer to page 36.) <MUH-A30WV> LEV connector (CN724) Fan motor connector (CN7) Varistor (NR62) } R.V. coil (CN72) Defrost interval time short pin(jpg, R87) (Refer to page 29.) + } 2V DC Fuse 3.5A / 250V J0 + 5V DC J40 (Refer to page 33 or 35.) } Varistor (NR6) } CN V AC (Refer to page 33 or 35.) Jumper wire for change in defrost setting (JRF, JRG) (Refer to page 29.) + } R60 0V DC (Refer to page 35.) 38

39 2 DISASSEMBLY INSTRUCTIONS <"Terminal with lock mechanism" Detaching points> In case of terminal with lock mechanism, detach the terminal as shown below. There are two types ( Refer to () and (2)) of the terminal with lock mechanism. The terminal with no lock mechanism can be removed by pulling it out. Check the shape of the terminal and work. () Slide the sleeve and check if there is a locking lever or not. (2) The terminal with this connector is a terminal with lock mechanism Sleeve Locking lever Slide the sleeve. 2Pull the terminal while pushing the locking lever. Connector Hold the sleeve, and pull out the terminal slowly. 2-. MUH-A8WV - E OUTDOOR UNIT OPERATING PROCEDURE. Removing the cabinet () Remove the screws of the cabinet. (2) Hold the down of the cabinet on the both side and remove the cabinet. Photo PHOTOS Photo 2 Screws of the cabinet Screws of the cabinet Service panel 2. Removing the deicer P.C. board () Remove the service panel and the cabinet. (2) Disconnect all the connectors and the terminals on the deicer P.C. board. (3) Remove the deicer P.C. board. Photo 3 Screw of the relay panel Deicer P.C. board Terminal blocks Relay panel Screw of the relay panel 39

40 OPERATING PROCEDURE PHOTOS 3. Removing the propeller and the outdoor fan motor () Remove the cabinet. (Refer to.) (2) Remove the propeller nut and the propeller. NOTE : Loose the propeller in the rotating direction for removal. When attaching the propeller, align the mark on the propeller and the motor shaft cut section. Set the propeller fan in position by using the cut on the shaft and the mark on the propeller. (3) Remove the clamp of outdoor fan motor lead wire and disconnect the outdoor fan motor connector. (4) Remove the screws fixing the outdoor fan motor. (5) Remove the outdoor fan motor. Photo 4 Propeller Set screws of the outdoor fan motor Lead clamps Propeller nut Set screws of the outdoor fan motor Outdoor fan motor 4. Removing the compressor () Remove the cabinet. (Refer to.) (2) Remove the relay panel. (3) Remove the soundproof felt. (4) Remove the terminal cover on the compressor. (5) Disconnect lead wires from the compressor. (6) Recover gas from the refrigerant circuit. (7) Disconnect the welded part of the discharge pipe. (8) Disconnect the welded part of the suction pipe. (9) Remove nuts fixing the compressor. (0) Remove the compressor. Photo 5 Discharge pipe Terminal cover NOTE Before using a burner, reclaim gas from the pipes until the pressure gauge shows 0 kg/cm 2 (0 MPa). Use the burner under the condition that gas can be recovered even when the inner pressure rises by heat. Compressor Suction pipe Compressor set nuts 40

41 2-2. MUH-A24WV - E MUH-A30WV - OUTDOOR UNIT OPERATING PROCEDURE.Removing the cabinet () 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) Remove the screws of the front panel. (8) Remove the front panel. (9) Remove the screws of the back panel. (0) Remove the back panel. E NOTE : These photos are MUH-A30WV. MUH-A24WV is almost the same as MUH-A30WV. Photo Screws of the cabinet PHOTOS Screw of the top panel Photo 3 Screw of the motor support Photo 2 Screws of the cabinet Screw of the service panel Screws of the back panel Screws of the front panel Screws of the top panel Set screws of the back panel Screw of the valve cover 2. Removing the deicer P.C. board () Remove the service panel and the cabinet. (2) Disconnect all the connectors and the terminals on the deicer P.C. board. (3) Remove the deicer P.C. board. Photo 4 Deicer P.C. board Terminal blocks Screws of the relay panel Screws of the relay panel 4

42 OPERATING PROCEDURE 3. Removing the propeller and the outdoor fan motor () Remove the cabinet. (Refer to.) (2) Remove the propeller nut and the propeller. NOTE : Loose the propeller in the rotating direction for removal. When attaching the propeller, align the mark on the propeller and the motor shaft cut section. Set the propeller fan in position by using the cut on the shaft and the mark on the propeller. (3) Remove the clamp of outdoor fan motor lead wire and disconnect the outdoor fan motor connector. (4) Remove the screws fixing the outdoor fan motor. (5) Remove the outdoor fan motor. Photo 5 Propeller nut PHOTOS Set screws of the outdoor fan motor Propeller Set screws of the outdoor fan motor 4. Removing the compressor () Remove the cabinet. (Refer to.) (2) Remove the relay panel. (3) Remove the soundproof felt. (4) Remove the terminal cover on the compressor. (5) Disconnect lead wires from the compressor. (6) Recover gas from the refrigerant circuit. (7) Disconnect the welded part of the discharge pipe. (8) Disconnect the welded part of the suction pipe. (9) Remove nuts fixing the compressor. (0) Remove the compressor. NOTE Before using a burner, reclaim gas from the pipes until the pressure gauge shows 0 kg/cm 2 (0 MPa). Use the burner under the condition that gas can be recovered even when the inner pressure rises by heat. Photo 6 Suction pipe Discharge pipe Terminal cover Compressor set nuts 42

43 3 PARTS LIST MUH-A8WV - E 3-. OUTDOOR UNIT STRUCTURAL PARTS, ELECTRICAL PARTS AND FUNCTIONAL PARTS 2 DEFROST THERMISTOR Part numbers that are circled are not shown in the illustration NO Part. E E E E E E E E E E E E E E E E E E E E E E E E E E E E E Part Name BACK PANEL CABINET GRILLE OUTDOOR HEAT EXCHANGER PROPELLER MOTOR SUPPORT COMPRESSOR RUBBER SET COMPRESSOR BASE STOP VALVE(GAS) STOP VALVE(LIQUID) SERVICE PANEL 4-WAY VALVE COMPRESSOR CAPACITOR OUTDOOR FAN MOTOR SURGE ABSORBER DEICER P.C. BOARD TERMINAL BLOCK TERMINAL BLOCK DEFROST THERMISTOR HANDLE CAPILLARY TUBE CAPILLARY TUBE CAPILLARY TUBE CAPILLARY TUBE FUSE R.V. COIL CHECK VALVE VARISTOR Symbol in Wiring Diagram MC C MF DSAR TB TB2 RT6 F6 2S4 NR6 Q'ty/unit MUH-A8WV- 3 2 E Remarks 3RUBBERS/SET RN96VHSHT {2.7 { /440V AC RA6V50-3P 2P {3.0 { {3.0 { {3.0 { {2.5 { V / 2A 43