Mitsubishi MUCFH-A18WV, MUCFH-A24WV Service Manual

SERVICE MANUAL

FLOOR AND CEILING TYPE AIR CONDITIONERS

HFC

utilized

R410A

Wireless type Models

Revision A:

● Power input of SPECIFICATION has modified. Please void OB337.

No. OB337

REVISED EDITION-A

MUCFH-A18WV MUCFH-A24WV -

Indication of model name

MUCFH-A18WV -

CONTENTS

1. TECHNICAL CHANGES ····································2

2. PART NAMES AND FUNCTIONS······················5

3. SPECIFICATION·················································5

4. NOISE CRITERIA CURVES·······························6

5. OUTLINES AND DIMENSIONS·························7

6. WIRING DIAGRAM ············································8

7. REFRIGERANT SYSTEM DIAGRAM················9

8. PERFORMANCE CURVES······························10

9. ACTUA TOR CONTROL····································18

10. SERVICE FUNCTIONS·····································18

11. TROUBLESHOOTING ······································19

12. DISASSEMBLY INSTRUCTIONS·····················29

13. PARTS LIST······················································33

NOTE:

•This service manual describes technical data of outdoor units. As for indoor units MCFH-A18WV- and MCFH-A24WV- refer to the

service manual OB336 REVISED EDITION-A.

E1E1

Refrigerating

oil

Refrigerant

New refrigerant

R410A

HFC-32: HFC-125 (50%:50%)

Pseudo-azeotropic refrigerant

Not included

A1/A1

72.6

-51.4

1.557 64

Non combustible

1730

From liquid phase in cylinder

Possible

Incompatible oil

Non Non

Previous refrigerant

R22

R22 (100%)

Single refrigerant

Included

86.5

-40.8

0.94

44.4

Non combustible

0.055 1700

Gas phase

Possible

Compatible oil

Light yellow

Non

Refrigerant Composition (Ratio) Refrigerant handling Chlorine Safety group (ASHRAE) Molecular weight Boiling point (:) Steam pressure [25:](Mpa) Saturated steam density [25:](Kg/K) Combustibility ODP w1 GWP w2 Refrigerant charge method Additional charge on leakage Kind Color Smell

w1:Ozone Destruction Parameter : based on CFC-11 w2 :Global Warmth Parameter : based on CO

Revision A:

•Power input of SPECIFICATION has modified.

MUH-A18WV - ➔ MUCFH-A18WV -

1. Capillary tube has changed.

2. Refrigerant filling capacity has changed. (1.75kg ➔ 1.85kg)

MUH-A24WV - ➔ MUCFH-A24WV -

1. Capillary tube has changed.

2. Refrigerant filling capacity has changed. (2.15kg ➔ 2.20kg)

TECHNICAL CHANGES

E1E1

INFORMATION FOR THE AIR CONDITIONER WITH R410A REFRIGERANT

• This room air conditioner adopts an HFC refrigerant (R410A) 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. 1 As R410A has working pressure approximate 1.6 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 R410Arefrigerant 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 R410A. (Refer to 2. Refrigerant

piping.)

4 Composition change may occur in R410A since it is a mixed refrigerant. When charging, charge liquid refrigerant to prevent

composition change.

NOTE : The unit of pressure has been changed to MPa on the international system of units(SI unit system).

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 refrigerating oil of the upper layer to flow back to the compressor.

Since refrigerant and refrigerating oil are compatible each, refrigerating oil backs to the compressor through the lower position oil back hole.

Compressor

Suction muffler

Oil back hole

Refrigerating oil

Refrigerant

Compressor

Suction muffler

Oil back hole

Refrigerating oil /Refrigerant

Compressor

-30 -20 -10 0 10 20

40 50 60

-0.5

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

(MPa [Gauge])

R410A R22

Conversion chart of refrigerant temperature and pressure

Saturated liquid pressure

(:)

R410A tools Can R22 tools be used?

Gas leak detector

R410A has high pressures beyond the measurement range of existing gauges. Port diameters have been changed to prevent any other refrigerant from being charged into the unit.

Hose material and cap size have been changed to improve the pressure resistance.

Dedicated for HFC refrigerant.

6.35 mm and 9.52 mm

Description

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).

Provided to prevent the back flow of oil. This adapter enables you to use vacuum pumps.

It is difficult to measure R410A with a charging cylinder because the refrigerant bubbles due to high pressure and high-speed vaporization

Yes

New

Gauge manifold

Charge hose

Torque wrench

Flare tool Flare gauge

Vacuum pump adapter

Electronic scale for refrigerant charging

No : Not Substitutable for R410A Yes : Substitutable for R410A

No 12.7 mm and 15.88 mm

The conversion factor is: 1(MPa [Gauge]) =10.2(kgf/ff[Gauge])

NOTE : 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/ff[Gauge])

1.Tools dedicated for the air conditioner with R410A refrigerant

The following tools are required for R410A refrigerant. Some R22 tools can be substituted for R410A 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 7/16 UNF with 20 threads to 1/2 UNF with 20 threads.

R410A

Pipe diameter

6.35

9.52

12.7

15.88

17 22 26 29

Dimension of flare nut

R22

17 22 24 27

Electronic scale for refrigerant charging

Outdoor unit

Refrigerant gas cylinder operating valve

Refrigerant gas cylinder for R410A with siphon

Refrigerant (liquid)

Service port

Gauge manifold valve (for R410A)

Union

Liquid pipe Gas pipe

Stop valve

Indoor unit

Charge hose (for R410A)

2.Refrigerant piping

Wall thickness

Outside diameter

Pipe

For liquid

For gas

6.35

9.52

12.7

15.88

0.8 mm

1.0 mm

Heat resisting foam plastic Specific gravity 0.045 Thickness 8 mm

Insulation material

1 Specifications

Use the refrigerant pipes that meet the following specifications.

• Use a copper pipe or a copper-alloy seamless pipe with a thickness of 0.8 mm (6.35, 9.52, 12.7), 1.0 mm (15.88). Never use any pipe with a thickness less than 0.8 mm (6.35, 9.52, 12.7), 1.0 mm (15.88), as the pressure resistance is insufficient.

2 Flaring work and flare nut

Flaring work for R410A pipe differs from that for R22 pipe. For details of flaring work, refer to Installation manual “FLARING WORK”.

3.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.

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

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(R410A) Refrigerating oil (Model) Thermistor RT61(at 0:)

r/h

K /h

A W %

rpm

kg cc

MUCFH-A18WV -

Single phase

230V, 50Hz

2,196

94 37

0.39

RN196VHSHT

1,300 C-R 1.80 C-S 3.00

RA6V50-OG

WHT-BLK 116

BLK-RED 111

850o605o290

47 52

828

1.85

520 (NEO22)

33.18

Cooling

4.8

2.4

8.01

1,730

7.62

2.65

Heating

5.0 —

8.38

1,810

7.99

2.65

MUCFH-A24WV -

Single phase

230V, 50Hz

2,760

98 74

0.58

NN29VBAHT

1,900 C-R 0.80 C-S 1.64

RA6V85-AB

WHT-BLK 63 BLK-YLW 30

YLW-RED 63

840o850o330

74 53

730

2.20

1,200 (NEO22)

33.18

Cooling

6.0

3.1

10.51 2,370

9.93

2.45

Heating

6.8 —

11.71 2,640

11.13

2.50

Electrical

data

Compressor

Fan

motor

Special

remarks

Coefficient of performance(C.O.P)

Capacity

PART NAMES AND FUNCTIONS

OUTDOOR UNIT

MUCFH-A18WV -

ACCESSORIES

Item

Drain socket Drain cap [33 Drain cap [16

SPECIFICATION

Air inlet

Piping

Drain hose

Air outlet

Drain outlet

MUCFH-A18WV-

1 2 1

MUCFH-A24WV -

Q'ty

MUCFH-A24WV-

1 6 –

Air inlet

(back and side)

Air outlet

NOTE: Test conditions are based on ISO 5151.

Cooling : Indoor DB27°C WB19°C Heating : Indoor DB20°C WB 15.5°C

Outdoor DB35°C WB(24°C) Outdoor DB 7°C WB 6°C

Indoor-Outdoor piping length : 5m

NOISE CRITERIA CURVES

MUCFH-A18WV -

Test conditions, Cooling : Dry-bulb temperature 35: Wet-bulb temperature (24:)

Heating : Dry-bulb temperature 7: Wet-bulb temperature 6:

FAN SPEED

High

SPL(dB

(A))

LINE

NC-70

NC-60

NC-50

NC-40

NC-30

MUCFH-A24WV -

Test conditions, Cooling : Dry-bulb temperature 35: Wet-bulb temperature (24:)

Heating : Dry-bulb temperature 7: Wet-bulb temperature 6:

FAN SPEED

High

SPL(dB

(A))

LINE

NC-70

NC-60

NC-50

NC-40

NC-30

APPROXIMATE

THRESHOLD OF HEARING FOR CONTINUOUS

OCTAVE BAND SOUND PRESSURE LEVEL, dB re 0.0002 MICRO BAR

NOISE

63 125 250 500 1000 2000 4000 8000

BAND CENTER FREQUENCIES, Hz

NC-20

APPROXIMATE

THRESHOLD OF HEARING FOR CONTINUOUS

OCTAVE BAND SOUND PRESSURE LEVEL, dB re 0.0002 MICRO BAR

NOISE

63 125 250 500 1000 2000 4000 8000

BAND CENTER FREQUENCIES, Hz

OUTDOORUNIT

MICROPHONE

NC-20

OUTLINES AND DIMENSIONS

OUTDOOR UNIT

MUCFH-A18WV -

Drainage hole [16.2

248

Air in

Drainage 3holes [33

605

292

MUCFH-A24WV -

299

355

350

515

Air in

Air out

183

500 850

290

310

157

100

REQUIRED SPACE

100mm or more

REQUIRED SPACE

100mm or more

345

161

500mm or more

Service panel

Liquid refrigerant pipe joint

Refregerant pipe (flared) [6.35

35-

30-

Gas refregerant pipe joint

Refregerant pipe (flared) [12.7

Open as a rule 500mm or more if the front and both sides are open

100mm or more

100mm or more 200mm or more if there are obstacles to both sides

Unit: mm

350mm or more

330

850

430

121

500

840

360

Open as a rule 500mm or more if the back,

both sides and top are open

155

198

350mm or more

Service panel

Liquid refrigerant pipe joint Refrigerant pipe (flared) [6.35

30-

35-

Gas refrigerant pipe joint Refrigerant pipe (flared) [15.88

WIRING DIAGRAM

MUCFH-A18WV -

OUTDOOR UNIT

TO INDOOR UNIT CONNECTING 12V

CIRCUIT BREAKER

POWER SUPPLY

~ /N

50Hz

230V

SYMBOL

COMPRESSOR CAPACITOR

C65

DSAR

F61

NOTES:

OUTDOOR FAN CAPACITOR SURGE ABSORBER FUSE (2A) COMPRESOR (INNER PROTECTOR)

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 below indicate. : Terminal block

NAME

: Connector

MODEL WIRING DIAGRAM

TB2

TB1

BRN

BLU

GRN/YLW

SYMBOL

NR61

RT61

SR61,SR62

T61

RED

BLK BRN

RT61

CN661

2 3

CN730

DSAR

F61

TAB20

T61

52C

BLU

NAME OUTDOOR FAN MOTOR (INNER PROTECTOR) VARISTOR DEFROST THERMISTOR SOLID STATE RELAY TRANSFORMER

21S4

CN721

SR62

SR61

NR61

DEICER P.C.BOARD

WHT

RED

BLK

SYMBOL

TB1,TB2

21S4

52C

WHT

BLK

RED

ORN

CN711

1 2 3

C65

TERMINAL BLOCK R.V. COIL COMPRESSOR CONTACTOR

WHT

BLK

RED

NAME

MUCFH-A24WV -

OUTDOOR UNIT

CIRCUIT BREAKER

~ /N 230V 50Hz

POWER SUPPLY

12V

TO INDOOR UNIT CONNECTING

TB1

L N

GRN/YLW

TB2

BRN

BLU

DSAR

BRN

BLU

RT61

CN661

BRN

BLU

X52X62

DEICER P.C. BOARD

52C

MODEL WIRING DIAGRAM

YLW

BLK

WHT

ORN

RED

3456

RED

ORN

CN730 F61

RED

BLK

CN721

TAB52

1 2 3

7 5 3 1

21S4

BLU

RED

BLU

YLW

123

SR61

T61

NR61

WHT

A1 A2

52C

BLK

WHT

CN711

X62

COM

X52

COM

SYMBOL

C1 C2

DSAR

F61

MC MF

NR61

RT61

SR61

TB1 TB2 T61 X52 X62

21S4

52C

NAME COMPRESSOR CAPACITOR OUTDOOR FAN CAPACITOR SURGE ABSORBER FUSE (3.15A) 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

NOTES:

1.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

REFRIGERANT SYSTEM DIAGRAM7

MUCFH-A18WV -

OUTDOOR UNIT

Refrigerant pipe [12.7 (with heat insulator)

Refrigerant pipe[6.35 (with heat insulator)

Flared connection

Stop valve (with service port)

Capillary tube

[2.5o[0.6o1,000

Receiver

Stop valve

Strainer

4- way valve

Capillary tube

[3.0o[1.6o650

#100

Check valve

Oil separator #100

Compressor

Capillary tube

Refrigerant flow in cooling Refrigerant flow in heating

Defrost thermistor RT61

R.V. coil Heating ON Cooling OFF

[3.0o[1.6o500

Unit:mm

Outdoor heat exchanger

Capillary tube

[3.0o[1.6o750

(2 pcs)

MUCFH-A24WV -

OUTDOOR UNIT

Refrigerant pipe [15.88 (with heat insulator)

Refrigerant pipe [6.35 (with heat insulator)

Flared connection

Stop valve (with service port)

Muffler

Receiver

Stop valve

Strainer

4- way valve

Capillary tube

[3.0X[2.0X400

#100

Check valve

Muffler

#100

Compressor

Capillary tube [3.0X[2.0X800

Refrigerant flow in cooling Refrigerant flow in heating

Outdoor heat exchanger

Defrost thermistor RT61

R.V. coil Heating ON Cooling OFF

A: Refrigerant piping Max.length 25m

W Max. Height

difference

10m

MAX. REFRIGERANT PIPING LENGTH & MAX. HEIGHT DIFFERENCE

Model

MUCFH-A18WV MUCFH-A24WV -

wIt does not matter which unit is higher.

Refrigerant piping MAX. length :mm

E1 E1

Piping size O.D. : mm

Gas

{12.7

{15.88

Liquid {6.35

ADDITIONAL REFRIGERANT CHARGE (R410A : g)

If pipe length exceeds 7m, additional refrigerant (R410A) charge is required.

Models

MUCFH-A18WV MUCFH-A24WV -

Calculation : ✕g=20g/m✕(Refrigerant piping length (m)-7)

PERFORMANCE CURVES

E1 E1

MUCFH-A18WV - MUCFH-A24WV -

The standard data contained in these specifications apply only to the operation of the air conditioner under normal condition.

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.

Outdoor unit:

precharged

1,850 2,200

E1E1

Refrigerant piping length (one way)

10m

15m

160

20m

260

25m

360

(1) GUARANTEED VOLTAGE

198~264V, 50Hz

(2) AIR FLOW

Air flow should be set at MAX.

(3) MAIN READINGS

COOLING (1) 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

Indoor air wet/dry-bulb temperature difference on the left side of the chart on 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.

HEATING (1) Indoor intake air dry-bulb temperature : ˚CDB (2) Indoor outlet air dry-bulb temperature : ˚CDB (3) Outdoor intake air wet-bulb temperature : ˚CWB (4) Total input : W

How to measure the indoor air wet-bulb/dry-bulb temperature difference

1. Attach at least 2 sets of wet and dry-bulb thermometers to the indoor air inlet 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 inlet.

Cover the thermometers to prevent direct rays of the sun.

3. Check that the air filter is cleaned.

4. Open windows and doors of the 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.

Air in

INDOOR UNIT

Air out

11.1

10.2

9.2

8.3

7.5

6.6

FRONT VIEW

14.7

13.4

12.1

10.9

9.7

8.5

Wet and dry-bulb thermometers

OUTDOOR UNIT

Wet and dry-bulb thermometers

BACK VIEW

MCFH-A18WV- E1

MUCFH-A18WV- E1

MUCFH-A24WV- E1

MCFH-A24WV- E1

31.8

23.4

29.3

21.6

26.9

19.8

24.4

18.0

22.0

16.2

19.5

14.4

17.1

12.6

14.7

10.8

MUCFH-A18WV- E1

MCFH-A24WV- E1

MUCFH-A24WV- E1

MCFH-A18WV- E1

OUTDOOR LOW PRESSURE AND OUTDOOR UNIT CURRENT

COOL operation

1 Both indoor and outdoor units are under the same temperature/humidity condition.

Dry Bulb temperature (˚C)

20 25 30

Relative humidity (%)

50 60 70

+ 25 hidden pages