Mitsubishi MUZ-A18YV User manual

SERVICE MANUAL
CONTENTS
1. TECHNICAL CHANGES ····································2
2. PART NAMES AND FUNCTIONS······················5
3. SPECIFICATION·················································5
4. NOISE CRITERIA CURVES·······························8
5. OUTLINES AND DIMENSIONS ·························9
6. WIRING DIAGRAM ··········································10
7. REFRIGERANT SYSTEM DIAGRAM··············12
8. PERFORMANCE CURVES······························14
9. ACTUATOR CONTROL····································29
10. TROUBLESHOOTING······································30
11. DISASSEMBLY INSTRUCTIONS·····················44
12. PARTS LIST······················································48
Wireless type
Models
SPLIT-TYPE, HEAT PUMPAIR CONDITIONERS
MUZ-A18YV -
MUZ-A24YV -
MUZ-A26YV - E1
E1
E1
MUZ-A18YV -
MUZ-A24YV -
MUZ-A26YV - E1
E1
E1
Indication of
model name
HFC
utilized
R410A
Revision A:
● MUZ-A18YV -can be connected to
MCFZ-A18WV -.
● MUZ-A24YV -can be connected to
MCFZ-A24WV -.
E1
E1
E1
E1
No. OB346
REVISED EDITION-A
Please void OB346.
NOTE:
This service manual describes technical data of the outdoor units.
•As for indoor units MSZ-A18YV - , MSZ-A24YV - and MSZ-A26YV - , refer to the
service manual OB345.
•As for indoor units MCFZ-A18WV - and MCFZ-A24WV - , refer to the service manual
OB344 REVISED EDITION-A. E1E1
E1E1E1
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2
1TECHNICAL CHANGES
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
0
1730
From liquid phase in cylinder
Possible
Incompatible oil
Non
Non
Previous refrigerant
R22
R22 (100%)
Single refrigerant
Included
A1
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 CO2
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 air
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.
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])
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
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3
-30 -20 -10 0 10 20 30 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
(:)
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])
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 R410Awith a charging cylinder because the
refrigerant bubbles due to high pressure and high-speed vaporization
No
No
No
Yes
Yes
New
New
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 15.88mm
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.
2.Refrigerant piping
1Specifications
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.
Wall
thickness
Outside diameter
Pipe mm
For liquid
For gas
6.35
9.52
12.7
15.88
0.8 mm
0.8 mm
0.8 mm
1.0 mm
Heat resisting foam plastic
Specific gravity 0.045 Thickness 8 mm
Insulation material
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4
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)
R410A
Pipe diameter
mm
6.35
9.52
12.7
15.88
17
22
26
29
Dimension of flare nut
R22
17
22
24
27
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”.
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.
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5
PART NAMES AND FUNCTIONS
2
OUTDOOR UNIT
Air inlet
Piping
Air outlet
(back and side)
Drain hose
Drain outlet
ACCESSORIES
1
2
Drain socket
Drain cap [33 1
2
MUZ-A18YV - E1
MUZ-A24YV - E1
MUZ-A26YV - E1
Single phase
230V,50Hz
20
7.38
0.30
SNB130FLDH
850
U-V 0.45 W-U 0.45
V-W 0.45
PM8H60-UB
BLK-WHT 15.2
WHT-RED 15.2 RED-BLK15.2
840o850o330
53
2
1.8
450 (NEO22)
13.4
10.0
17.0
10.0
Cooling
5.0(0.9~5.9)
2.5
2,940/1,650W
6.62
1,500
98.5
6.32
3.21
53/51W
800/480W
Heating
5.9(0.9~7.8)
—
2,940/2,210W
7.38
1,670
98.4
7.08
3.41
55/53W
800/620W
Single phase
230V,50Hz
20
98
8.87
0.30
SNB130FLDH
850
U-V 0.45 W-U 0.45
V-W 0.45
PM8H60-UB
BLK-WHT 15.2
WHT-RED 15.2 RED-BLK15.2
840o850o330
53
2
1.8
450 (NEO22)
13.4
10.0
17.0
10.0
Cooling
4.8(10.9~5.5)
2.4
2,940/1,650W
7.76
1,750
7.46
2.62
53/51W
800/480W
Heating
6.0(0.9~7.5)
—
2,940/2,210W
8.87
2,000
8.57
2.88
55/53W
800/620W
Outdoor model
Function
Power supply
Capacity Rated frequency(Min.~Max.)
Dehumidification
Air flow(High/LowW)
Power outlet
Running current
Power input
Power factor
Starting current ✽1
Compressor motor current ✽1
Fan motor current
Model
Output
Winding
resistance(at 20:)
Model
Winding
resistance(at 20:)
Dimensions WOHOD
Weight
Sound level(High/LowW)
Fan speed(High/LowW)
Fan speed regulator
Refrigerant filling
capacity(R410A)
Refrigerating oil(Model)
Thermistor RT61(at 100:)
Thermistor RT62(at 25:)
Thermistor RT65(at 50:)
Thermistor RT68(at 25:)
kW
r/h
K/h
A
A
W
%
A
A
A
W
"
"
mm
kg
dB
rpm
kg
cc
k"
k"
k"
k"
Compressor
Fan motor
Special remarks
Coefficient of performance(C.O.P) ✽1
Capacity
Electrical data
MUZ-A18YV - E1
E1
MSZ-A18YV -
Indoor model MUZ-A18YV - E1
E1
MCFZ-A18WV -
Indoor model
NOTE : Test conditions are based on ISO 5151.
Cooling : Indoor DB 27:WB 19:
Outdoor DB 35:WB (24:)
Heating : Indoor DB 20:WB 15:
Outdoor DB 7:WB 6:
Refrigerant piping length (one way): 5m
✽1 Measured under rated operating frequency.
wReference value
3SPECIFICATION
MUZ-A18YV -
MUZ-A24YV -
MUZ-A26YV - E1
E1
E1
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6
NOTE : Test conditions are based on ISO 5151.
Cooling : Indoor DB 27:WB 19:
Outdoor DB 35:WB (24:)
Heating : Indoor DB 20:WB 15:
Outdoor DB 7:WB 6:
Refrigerant piping length (one way): 5m
✽1 Measured under rated operating frequency.
wReference value
Single phase
230V,50Hz
20
98.4
8.75
0.30
SNB130FLDH
850
U-V 0.45 W-U 0.45
V-W 0.45
PM8H60-UB
BLK-WHT 15.2
WHT-RED 15.2 RED-BLK15.2
840o850o330
53
2
1.8
450 (NEO22)
13.4
10.0
17.0
10.0
Cooling
6.0(0.9~6.7)
3.0
2,940/1,650W
8.49
1,921
8.19
3.02
53/51W
800/480W
Heating
6.8(0.9~8.1)
—
2,940/2,210W
8.75
1,981
8.45
3.32
55/53W
800/620W
Single phase
230V,50Hz
20
98
10.47
0.30
SNB130FLDH
850
U-V 0.45 W-U 0.45
V-W 0.45
PM8H60-UB
BLK-WHT 15.2
WHT-RED 15.2 RED-BLK15.2
840o850o330
53
2
1.8
450 (NEO22)
13.4
10.0
17.0
10.0
Cooling
5.5(0.9~6.1)
3.1
2,940/1,650W
10.38
2,340
10.08
2.27
53/51W
800/480W
Heating
6.4(0.9~7.9)
—
2,940/2,210W
10.47
2,360
10.17
2.62
55/53W
800/620W
Single phase
230V,50Hz
20
98.3
11.42
0.30
TNB220FMCH
1,300
U-V 1.41 W-U 1.41
V-W 1.41
PM8H60-UB
BLK-WHT 15.2
WHT-RED 15.2 RED-BLK15.2
840o850o330
58
2
2.0
870 (NEO22)
13.4
10.0
17.0
10.0
Cooling
7.1(0.9~8.3)
3.8
2,940/1,650W
10.75
2,431
10.45
2.84
53/51W
800/480W
Heating
8.1(0.9~9.6)
—
2,940/2,210W
11.42
2,581
11.12
3.06
55/53W
800/620W
Outdoor model
Function
Power supply
Capacity Rated frequency(Min.~Max.)
Dehumidification
Air flow(High/LowW)
Power outlet
Running current
Power input
Power factor
Starting current ✽1
Compressor motor current ✽1
Fan motor current
Model
Output
Winding
resistance(at 20:)
Model
Winding
resistance(at 20:)
Dimensions WOHOD
Weight
Sound level(High/LowW)
Fan speed(High/LowW)
Fan speed regulator
Refrigerant filling
capacity(R410A)
Refrigerating oil(Model)
Thermistor RT61(at 100:)
Thermistor RT62(at 25:)
Thermistor RT65(at 50:)
Thermistor RT68(at 25:)
kW
r/h
K/h
A
A
W
%
A
A
A
W
"
"
mm
kg
dB
rpm
kg
cc
k"
k"
k"
k"
Compressor
Fan motor
Special remarks
Coefficient of performance(C.O.P) ✽1
Capacity
Electrical data
MUZ-A24YV - E1
E1
MSZ-A24YV -
Indoor model MUZ-A26YV - E1
E1
MSZ-A26YV -
Indoor model
MUZ-A24YV - E1
E1
MCFZ-A24WV -
Indoor model
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7
OUTDOOR UNIT
Model
Item
Smoothing capacitor
Current transformer
Current transformer
Fuse
Fuse
Fet array
High pressure switch
Power transistor module
Reactor
Expansion valve
Power factor controller
Resistor
Resistor
Resistor
Solenoid coil relay
Terminal block
Terminal block
Relay
R.V. coil
MUZ-A18YV - E1
(CB1,2,3)
(CT1,2)
(CT61)
(F801, F912)
(F911)
(HC932)
(HPS)
(IPM)
(L)
(LEV)
(PFC)
(R64)
(R934A,B)
(RS1~4)
(SSR61)
(TB1)
(TB2)
(X64)
(21S4)
MUZ-A24YV - E1 MUZ-A26YV - E1
560+450V
ETQ19Z68AY
ETQ19Z53AY
250V 3.15A
250V 1A
SLA5075
PS21244-A
340µH 20A
PS51259-A
10"20W
1.1"2W 2%
0.04"7W
TLP3506
3P
2P
G4A
LD30013
ACB-DB156
CAM-40YGME 12VDC
–
CAM-30YGME 12VDC
Specifications and rating conditions of main electric parts
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8
NOISE CRITERIA CURVES
4
COOLING
FUNCTION SPL(dB(A)) LINE
High
SPEED
HEATING
53
55
90
80
70
60
50
40
30
20
10 63 125 250 500 1000 2000 4000 8000
NC-60
NC-50
NC-40
NC-30
NC-20
NC-70
BAND CENTER FREQUENCIES, Hz
Test conditions,
Cooling : Dry-bulb temperature 35: Wet-bulb temperature (24:)
APPROXIMATE
THRESHOLD OF
HEARING FOR
CONTINUOUS
NOISE
Heating : Dry-bulb temperature 7: Wet-bulb temperature 6:
OCTAVE BAND SOUND PRESSURE LEVEL, dB re 0.0002 MICRO BAR
MUZ-A18YV -
MUZ-A24YV -
MUZ-A26YV - E1
E1
E1
OUTDOORUNIT
MICROPHONE
1m
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9
5OUTLINES AND DIMENSIONS
Unit: mm
OUTDOOR UNIT
MUZ-A18YV -
MUZ-A24YV -
MUZ-A26YV - E1
E1
E1
30-
35-
155
90
198
40
515
299
66
34
51
330
360
850
430
500 80
121
840
Open as a rule
500mm or more if
the front and both
sides are open
100mm 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
100mm or more
Service panel
Gas refrigerant
pipe joint
Refrigerant pipe
(flared) [12.7 (MUZ-A18YV)
[15.88 (MUZ-A24/A26YV)
Liquid refrigerant
pipe joint
Refrigerant pipe
(flared) [6.35 (MUZ-A18/A24YV)
[9.52 (MUZ-A26YV)
REQUIRED SPACE
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10
WIRING DIAGRAM
6
MUZ-A18YV -
MUZ-A24YV -E1
E1
PFC
GRN
LD9 POWER
BOARD RT65
21
CN3
RED
WHT
RS2 RS1
R64
RS3 RS4
F801
CN901
NR63
ELECTRONIC P.C. BOARD CONTROL
CB1
CB2
CB3
HC932
IPM
NF
NOISE FILTER P.C. BOARD
BLK BLK BLK
BLK WHT RED YLW BLU ORN PNK GRY
BLU RED
GRN
GRN
BLU
BLU
BLK
BLK
BLK
BLK
BLK
BLK
BLK
BLK
BLK
BLK
BLK RED
BRN
BLU
LCT2
CT1
SSR61
U
6
CN795
4123 78
CN661
W
CN4
TB2
3
TO INDOOR UNIT CONNECTING 12V
1
CN601
3
N
1 567
CN702
5321 CN781 13
CN701
12
12
CN931
LD1LD2
T801 R934A
R934B
CN801
23134512
MF
CN932
4X64
5123
LDE2
13
CT61
TAB1
F912
F911
LDE1
CN912
21S4
POWER SUPPLY ~/N 230V 50Hz
TAB2
GRN/YLW
NPE
L
TB1
CIRCUIT BREAKER 4
1
RED YLW
3 2
RED S
R
21
CN903
21
CN902
21
CN5
6543 1
CN2 27
TAB4 YLW VMC
W
U
V
WHT
RT62 RT61 RT68 LEV
:Terminal block :Connector 3.Symbols below indicate. 2.Use copper conductors only (for field wiring).
diagram for servicing.
refer to the indoor unit electric wiring
1.About the indoor side electric wiringNOTES:
SYMBOL
NAME
SYMBOL
NAME
CURRENT TRANSFORMER
FUSE (250V 3.15A)
FUSE (250V 1A)
LEV EXPANSION VALVE COIL
LREACTOR
IPM POWER TRANSISTOR MODULE
CT61
CT1, 2 CURRENT TRANSFORMER
HC932 FET ARRAY
F912
F911
F801 FUSE (250V 3.15A)
SMOOTHING CAPACITOR
CB1~3
OUTDOOR FAN MOTOR (INNER FUSE)
POWER FACTOR CONTROLLER
NOISE FILTER
RT61
DISCHARGE TEMPERATURE THERMISTOR
RS1~4 RESISTOR
R934A, B
RESISTOR
MF
MC COMPRESSOR
R64 RESISTOR
PFC
NF
NR63 VARISTOR
FIN TEMPERATURE THERMISTOR
SOLENOID COIL RELAY
21S4 R.V. COIL
X64 RELAY
TB1 TERMINAL BLOCK TB2 TERMINAL BLOCK
RT65
T801 TRANSFORMER
SSR61
RT68 OUTDOOR HEAT EXCHANGER
TEMPERATURE THERMISTOR
DEFROST THERMISTOR
RT62
NAME
SYMBOL
MODELS WIRING DIAGRAM
OUTDOOR UNIT
OB346A --1qxp 04.6.14 1:20 PM Page 10