Mitsubishi MUCFH-A18WV, MUCFH-A24WV Service Manual

Revision A:

FLOOR AND CEILING TYPE AIR CONDITIONERS

● Power input of SPECIFICATION has modified.

Please void OB337.

	HFC	No. OB337
		REVISED EDITION-A
	utilized
SERVICE MANUAL	R410A
Wireless type
Models
MUCFH-A18WV - E1
MUCFH-A24WV - E1

CONTENTS

1.TECHNICAL CHANGES ················

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

3.SPECIFICATION····················

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

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

6.WIRING DIAGRAM ··················

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

8. PERFORMANCE CURVES ···············

Indication of model name 9. ACTUATOR CONTROL·················

MUCFH-A18WV - E1 10. SERVICE FUNCTIONS·················

11.TROUBLESHOOTING ·················

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

13.PARTS LIST······················

NOTE:

•This service manual describes technical data of outdoor units.

As for indoor units MCFH-A18WV- E1 and MCFH-A24WV- E1 refer to the service manual OB336 REVISED EDITION-A.

Revision A:

•Power input of SPECIFICATION has modified.

1 TECHNICAL CHANGES

MUH-A18WV - E1 MUCFH-A18WV - E1

1.Capillary tube has changed.

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

MUH-A24WV - E1 MUCFH-A24WV - E1

1.Capillary tube has changed.

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

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.

1As 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.

2Take sufficient care not to allow water and other contaminations to enter the R410A refrigerant during storage and installation, since it is more susceptible to contaminations than R22.

3For refrigerant piping, use clean, pressure-proof parts/materials specifically designed for R410A. (Refer to 2. Refrigerant piping.)

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

Refrigerant

Refrigerating

oil

	New refrigerant	Previous refrigerant
Refrigerant	R410A	R22
Composition (Ratio)	HFC-32: HFC-125 (50%:50%)	R22 (100%)
Refrigerant handling	Pseudo-azeotropic refrigerant	Single refrigerant
Chlorine	Not included	Included
Safety group (ASHRAE)	A1/A1	A1
Molecular weight	72.6	86.5
Boiling point (:)	-51.4	-40.8
Steam pressure [25:](Mpa)	1.557	0.94
Saturated steam density [25:](Kg/K)	64	44.4
Combustibility	Non combustible	Non combustible
ODP w1	0	0.055
GWP w2	1730	1700
Refrigerant charge method	From liquid phase in cylinder	Gas phase
Additional charge on leakage	Possible	Possible
Kind	Incompatible oil	Compatible oil
Color	Non	Light yellow
Smell	Non	Non

w1 :Ozone Destruction Parameter	: based on CFC-11
w2 :Global Warmth Parameter	: based on CO2

2

New Specification

Current Specification

The incompatible refrigerating oil easily separates from

Since refrigerant and refrigerating oil are compatible each,

refrigerant and is in the upper layer inside the suction muffler.

refrigerating oil backs to the compressor through the lower

Raising position of the oil back hole enables to back the

position oil back hole.

Compressor

refrigerating oil of the upper layer to flow back to the

Compressor

Compressor

Oil back hole

compressor.

Suction muffler

Suction muffler

Refrigerating oil

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: 1(MPa [Gauge]) =10.2(kgf/f [Gauge])

Conversion chart of refrigerant temperature and pressure

(MPa [Gauge])
	4.0
	3.5
pressure							R410A
	3.0						R22
liquid	2.5
	2.0
	1.5
Saturated
	1.0
	0.5
	0.0
	-0.5
	-30 -20			-10 0 10 20 30 40 50 60

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/f [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 tools	Can R22 tools be used?	Description
			R410A has high pressures beyond the measurement range of existing
	Gauge manifold	No	gauges. Port diameters have been changed to prevent any other refrigerant
			from being charged into the unit.
	Charge hose	No	Hose material and cap size have been changed to improve the pressure
			resistance.
	Gas leak detector	No	Dedicated for HFC refrigerant.
	Torque wrench	Yes	6.35 mm and 9.52 mm
		No	12.7 mm and 15.88 mm
	Flare tool	Yes	Clamp bar hole has been enlarged to reinforce the spring strength in the tool.
	Flare gauge	New	Provided for flaring work (to be used with R22 flare tool).
	Vacuum pump	New	Provided to prevent the back flow of oil. This adapter enables you to use
	adapter		vacuum pumps.
	Electronic scale for	New	It is difficult to measure R410A with a charging cylinder because the
	refrigerant charging		refrigerant bubbles due to high pressure and high-speed vaporization

No : Not Substitutable for R410A Yes : Substitutable for R410A 3

2.Refrigerant piping

1Specifications

Use the refrigerant pipes that meet the following specifications.

	Pipe	Outside diameter	Wall	Insulation material
		mm	thickness
	6.35		0.8 mm
	For liquid			Heat resisting foam plastic
			0.8 mm
	9.52
	12.7		0.8 mm	Specific gravity 0.045 Thickness 8 mm
	For gas

15.881.0 mm

•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.

2Flaring 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”.

Pipe diameter	Dimension of flare nut
mm	R410A		R22
6.35	17		17
9.52	22		22
12.7	26		24
15.88	29		27

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.

Union

Stop valve

Indoor unit

Liquid pipe

Refrigerant gas cylinder operating valve

Gas pipe

Outdoor unit

Service port

Gauge manifold valve (for R410A)

Charge hose (for R410A)

Refrigerant gas cylinder for R410A with siphon

Refrigerant (liquid)

Electronic scale for refrigerant charging

4

2 PART NAMES AND FUNCTIONS

	OUTDOOR UNIT
	MUCFH-A18WV - E1		MUCFH-A24WV - E1
		Air inlet	Air inlet
			(back and side)
		Piping
		Drain hose
		Air outlet
			Air outlet
		Drain outlet
	ACCESSORIES
	Item		Q'ty
		MUCFH-A18WV- E1	MUCFH-A24WV- E1
	Drain socket
		1	1
	Drain cap [33	2	6
	Drain cap [16	1	–

3 SPECIFICATION

Outdoor model

Function

Power supply

	Capacity		Air flow(High)	K /h
			Capacity	kW
			Dehumidification	r/h
			Power outlet	A
	Electrical	data	Running current	A
			Power input	W
			Power factor	%
			Starting current	A
			Compressor motor current	A
			Fan motor current	A
	Coefficient of performance(C.O.P)
	Compressor		Model
			resistance(at 20:)	W
			Output
			Winding	"
	Fan	motor	Model	"
			Winding
			resistance(at 20:)
			Dimensions WOHOD	mm
			Weight	kg
			Sound level(High)	dB
		remarks	Fan speed(High)	rpm
	Special		Fan speed regulator
			capacity(R410A)
			Refrigerant filling	kg
			Refrigerating oil (Model)	cc
			Thermistor RT61(at 0:)	k"

NOTE: Test conditions are based on ISO 5151. Cooling : Indoor DB27°C WB19°C

Outdoor DB35°C WB(24°C) Indoor-Outdoor piping length : 5m

MUCFH-A18WV - E1			MUCFH-A24WV - E1
Cooling	Heating		Cooling	Heating
Single phase				Single phase
230V, 50Hz				230V, 50Hz
4.8	5.0		6.0	6.8
2.4	—		3.1	—
2,196				2,760
15				25
8.01	8.38		10.51	11.71
1,730	1,810		2,370	2,640
94				98
37				74
7.62	7.99		9.93	11.13
0.39				0.58
2.65	2.65		2.45	2.50
RN196VHSHT				NN29VBAHT
1,300				1,900
C-R 1.80				C-R 0.80
C-S 3.00				C-S 1.64
RA6V50-OG				RA6V85-AB
WHT-BLK 116			WHT-BLK 63 BLK-YLW 30
BLK-RED 111				YLW-RED 63
850o605o290			840o850o330
47				74
52				53
828				730
1				1
1.85				2.20
520 (NEO22)			1,200 (NEO22)
33.18				33.18
Heating : Indoor	DB20°C	WB 15.5°C

Outdoor DB 7°C WB 6°C

5

4 NOISE CRITERIA CURVES

MUCFH-A18WV - E1						MUCFH-A24WV - E1
	FAN SPEED	SPL(dB(A))	LINE				FAN SPEED	SPL(dB(A))	LINE
	High	52					High	53
Test conditions,						Test conditions,

		Cooling : Dry-bulb temperature 35: Wet-bulb temperature (24:)
	90	Heating : Dry-bulb temperature				7: Wet-bulb temperature				6:		90
BAR											BAR
MICRO	80										MICRO	80
dB re 0.0002	70									NC-70	dB re 0.0002	70
	60											60
LEVEL,											LEVEL,
										NC-60
	50											50
PRESSURE											PRESSURE
										NC-50
	40											40
										NC-40
SOUND											SOUND
	30											30
										NC-30
BAND											BAND
	20	APPROXIMATE										20
OCTAVE		THRESHOLD OF									OCTAVE
		HEARING FOR								NC-20
		CONTINUOUS
	10	NOISE										10
		63	125	250	500	1000	2000	4000	8000

Cooling : Dry-bulb temperature	35:	Wet-bulb temperature (24:)
Heating : Dry-bulb temperature	7:	Wet-bulb temperature 6:

							NC-70
							NC-60
							NC-50
							NC-40
							NC-30
APPROXIMATE
THRESHOLD OF
HEARING FOR							NC-20
CONTINUOUS
NOISE
63	125	250	500	1000	2000	4000	8000

BAND CENTER FREQUENCIES, Hz

BAND CENTER FREQUENCIES, Hz

OUTDOORUNIT

1m

MICROPHONE

6

5	OUTLINES AND DIMENSIONS
OUTDOOR UNIT
MUCFH-A18WV - E1						REQUIRED SPACE
		350	20					moreor
	Drainage	355
	hole [16.2	Air in						100mm
	35
	90					100mm	or
248				290	310	345	more
	Air in
								more
								or
	Drainage		Air out	50				500mm
	3holes [33
					30		Service panel
								Liquid refrigerant
								pipe joint
								Refregerant pipe
605								(flared) [6.35
							-	-
	292						30	35
				157	100
							Gas refregerant
	20		183				pipe joint
						161 Refregerant pipe

(flared) [12.7

Unit: mm

ormore 100mm

350mm	or
	more

500
850	74
MUCFH-A24WV - E1	REQUIRED SPACE
515

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

299	40		100mm or more
66
			200mm or more if
		100mm or more
51 34			there are obstacles
			to both sides
330		360
500		Open as a rule
		500mm or more if the back,	350mm or more
840		80 both sides and top are open
121

		Service panel
		Liquid refrigerant
850		pipe joint
		Refrigerant pipe
		(flared) [6.35
430		-
		30
		-
155		35
	90	Gas refrigerant
		pipe joint
	198	Refrigerant pipe
		(flared) [15.88
7

6 WIRING DIAGRAM

MUCFH-A18WV - E1

MODEL WIRING DIAGRAM

OUTDOOR UNIT

21S4

MF

TB2

RT61

RED

ORN WHT BLK

TO

3

RED

CN730

1

CN661

CN721

1 2 3 4

INDOOR UNIT

N

BLK

2

CN711

CONNECTING

SR62

3

WHT

12V

TB1 BRN

1

CIRCUIT BREAKER

SR61

2

BLK

L

BRN

DSAR

RED

F61

NR61

3

POWER SUPPLY

N BLU

T61

C65

~ /N

TAB20

52C

230V

50Hz

PE

GRN/YLW

4

3

DEICER P.C.BOARD

C1

WHT

C

BLU

RED

MC

R

BLK

S

SYMBOL	NAME		SYMBOL	NAME	SYMBOL	NAME
C1	COMPRESSOR CAPACITOR		MF	OUTDOOR FAN MOTOR (INNER PROTECTOR)	TB1,TB2	TERMINAL BLOCK
C65	OUTDOOR FAN CAPACITOR		NR61	VARISTOR	21S4	R.V. COIL
DSAR	SURGE ABSORBER		RT61	DEFROST THERMISTOR	52C	COMPRESSOR CONTACTOR
F61	FUSE (2A)		SR61,SR62	SOLID STATE RELAY
MC	COMPRESOR (INNER PROTECTOR)		T61	TRANSFORMER
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 below indicate.
	: Terminal block	: Connector

MUCFH-A24WV - E1

MODEL WIRING DIAGRAM

OUTDOOR UNIT

DSAR

RT61

YLWYLW

BLKBLK

MF

BRN

WHTWHT

ORN

RED

6

5

4

3

2

1

RED

C2

CIRCUIT BREAKER

ORN

CN711CN721

SUPPLYPOWER

L

TB1

CN661

1

2

3

50Hz230V/N~

GRN/YLW

1

X62

X52

X62

21S4

N

SR61

2

COM

NO

3

PE

X52

TAB52

COM

NO

CN730 7

DEICER

T61

5

NR61

F61

3

CONNECTING

3 TB2

P.C. BOARD

1

BRN

3

4

WHT

C

BRN

BLU

UNIT

12V

N

BLU

52C

C1

S

MC R

RED

INDOOR

BLK

BLU

A1 52C

A2

BLU

TO

RED

BLU

SYMBOL	NAME
C1	COMPRESSOR CAPACITOR
C2	OUTDOOR FAN CAPACITOR
DSAR	SURGE ABSORBER
F61	FUSE (3.15A)
MC	COMPRESSOR (INNER PROTECTOR)
MF	OUTDOOR FAN MOTOR (INNER PROTECTOR)
NR61	VARISTOR
RT61	DEFROST THERMISTOR
SR61	SOLID STATE RELAY
TB1	TERMINAL BLOCK
TB2	TERMINAL BLOCK
T61	TRANSFORMER
X52	CONTACTOR
X62	R. V. COIL RELAY
21S4	R. V. COIL
52C	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

8

7 REFRIGERANT SYSTEM DIAGRAM

MUCFH-A18WV - E1			Unit:mm
OUTDOOR UNIT
Refrigerant pipe [12.7	4- way valve
(with heat insulator)
Stop valve		Oil separator
(with service port)		#100	Outdoor
Flared connection		Defrost	heat
			exchanger
		thermistor
		RT61
	Capillary tube
	[2.5o[0.6o1,000
		Compressor

Flared connection

Refrigerant pipe[6.35 (with heat insulator)

Receiver

Stop valve

Capillary tube [3.0o[1.6o650

Strainer
#100	Check valve

Capillary tube [3.0o[1.6o750 (2 pcs)

R.V. coil Heating ON

Cooling OFF

Capillary tube [3.0o[1.6o500

Refrigerant flow in cooling

Refrigerant flow in heating

MUCFH-A24WV - E1

OUTDOOR UNIT

Refrigerant pipe [15.88		4- way valve
(with heat insulator)
	Stop valve
	(with service port)			Outdoor
Flared connection			Muffler	heat
		Muffler	#100	exchanger

	Compressor	Defrost
		thermistor
		RT61

Flared connection	Capillary tube
	[3.0X[2.0X400
Receiver
Stop valve	Strainer	Capillary tube	R.V. coil
Refrigerant pipe [6.35	#100	[3.0X[2.0X800	Heating ON
	Check valve		Cooling OFF

(with heat insulator)

Refrigerant flow in cooling

Refrigerant flow in heating

9

MAX. REFRIGERANT PIPING LENGTH & MAX. HEIGHT DIFFERENCE

Model	Refrigerant piping	Piping size O.D. : mm
	MAX. length :mm
	A	Gas		Liquid
MUCFH-A18WV - E1	25	{12.7		{6.35
MUCFH-A24WV - E1		{15.88

wIt does not matter which unit is higher.

Max. Height	difference	10m
W

A: Refrigerant piping Max.length 25m

ADDITIONAL REFRIGERANT CHARGE (R410A : g)

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

	Models	Outdoor unit:		Refrigerant piping length (one way)
		precharged	7m	10m	15m	20m	25m
	MUCFH-A18WV - E1	1,850	0	60	160	260	360
	MUCFH-A24WV - E1	2,200

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

8 PERFORMANCE CURVES

MUCFH-A18WV - E1 MUCFH-A24WV - E1

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.

(1) GUARANTEED VOLTAGE

198~264V, 50Hz

(2) AIR FLOW

Air flow should be set at MAX.

(3) MAIN READINGS

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

10

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.

	INDOOR UNIT	OUTDOOR UNIT
	Air out	Wet and dry-bulb
		thermometers

Air in

FRONT VIEW

11.1 14.7

10.2 13.4

9.2 12.1

8.3 10.9

7.5 9.7

6.6 8.5

MCFH-A18WV- E1

MUCFH-A18WV- E1

MCFH-A24WV- E1

MUCFH-A24WV- E1

23.431.8

21.629.3

19.826.9

18.0

24.4

16.222.0

14.419.5

12.617.1

10.814.7

MCFH-A18WV- E1	MUCFH-A18WV- E1	MCFH-A24WV- E1	MUCFH-A24WV- E1

Wet and dry-bulb

thermometers BACK VIEW

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)	Relative humidity (%)
20	50
25	60
30	70

11