Mitsubishi Heavy Industries SRK20MA-S User manual

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Mitsubishi Heavy Industries Air Conditioners
Technical Manual
Manual Number: 2011 No. W2-01
Variable Frequency Wall Mounted Type
Room Air Conditioners
(Split system, heat pump type)
SRK20MA-S/SRC20MA-S
SRK25MA-S/SRC25MA-S
SRK35MA-S/SRC35MA-S
SRK50MA-S/SRC50MA-S
(R410A Refrigerant Used)
MITSUBISHI HEAVY INDUSTRIES, LTD.

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Table of Contents
1. GENERAL INFORMATION…………..……………………….……1
1.1 Features……………………………………..……………………..…1
1.2 Model identification………………………………………………1
2 MODEL SELECTION…………………………………………………2
2.1 Model function..…………..…….……..………………………..……2
2.2 Range of usage……………………………………………..………6
2.3 Outline drawing……………………………..……………………..…6
2.4 Cooling cycle system diagram…….………………..…………...…8
2.5 Performance curve……………………………………………………9
3 ELECTRICAL WIRING DIAGRAM……………………………….10
4 NAME OF EACH PART AND ITS FUNCTION………….12
4.1 Name of each part………………………….......…………………....15
4.2 Emergency switch………………………….......…………………....15
4.3 Automatic restart……………..…………..………………………..15
4.4 Key lock………….…………..……..……………………………..15
4.5 CLEAN operation………………...……..…………………………..15
4.6 SLEEP operation……..……..…………………………….……..16
4.7 Timing off………...............................................................16
4.8 Timing on ...........................................................................17
4.9 Programmed timer........................................................................17
4.10 Current time setting.....................................................................18
4.11 HI POWER operation....................................................................18
4.12 JET operation.........................................................................18
4.13 POWER SAVE operation.................................................................19
4.14 Air direction adjustment..............................................................19
4.15 Area setting…......................................................................20
4.16 Installation location setting.............................................................20
4.17 Outline of automatic operation..................................................20

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4.18 Outline of drying operation..................................................21
4.19 Outline of defrosting operation.................................................21
4.20 Outline of vertical and horizontal flaps control................................23
4.21 Outline of electronic expansion valve (EEV) control.....................24
4.22 Outline of compressor control.........................................24
4.23 Outline of outdoor fan control.........................................24
4.24 Outline of indoor fan control.........................................25
5 INSTALLATION................................................................................27
5.1 Selection of installation location.................................................29
5.2 Installation of indoor unit..................................................................30
5.3 Installation of outdoor unit...............................................................33
5.4 Pipe connection.................................................................................33
5.5 Precautions for wireless remote controller operation.........................35
5.6 Standard running data........................................................................36
6 MAINTENANCE................................................................................37
6.1 Electrical parts failure diagnosis method.....................................37
6.2 Servicing.............................................................................................58
7 SERVICING MANUAL.......................................................................59
8 MOUNT ASSEMBLY…………………………...........................74
8.1 Indoor unit.........................................................................................74
8.2 Outdoor unit......................................................................................90

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1 GENERALINFORMATION
1.1 Features
(1) Inverter
● Heating/cooling
The rotate speed of the compressor is changed steplessly in relation to varying load, and is linked
with the fans of indoor and outdoor units controlled by the changes of frequency, thus controls
the power.
● Allowing quick heating/cooling operation during start-up period.
The room temperature is kept constant through fine-tuned control after the machine is stabilized.
(2) Fuzzy control: According to the fuzzy control technology, the indoor temperature and humidity,
etc. are obtained through dynamic analysis to accurately regulate the rotate speeds
of the compressor and the fan to realize precise temperature control.
(3) Comfort: 3D air blowing, sleep mode, and other air blowing modes.
(4) Humanization: Room temperature displaying, key lock, concentrated/area air blowing.
(5) Life: Actual service life: over 20,000 hours; Working life: over 100,000 hours; On/off of relay:
over 50,000 times; Continuous on of LED: over 50,000 hours; On/off of emergency switch:
over 10,000 times.
(4) Self diagnosis function: We will continuously provide the best services for our customers through
devices judging abnormal operation, as follows:
Indoor indication
Error
RUN lamp
TIMER lamp
Temp.
indication
Indoor
unit
Sensors
Indoor heat exchanger sensor error
1 time/8 sec.
ON
06
Indoor inlet air (room temp.) sensor error
2 times/8 sec.
--
Others
Indoor fan motor error
6 times/8 sec.
16
Display communication error
--
--
00
Outdoor unit
Sensors
Outdoor temp. sensor error
Continuous
flashing
1 time/8 sec.
38
Outdoor heat exchanger (liquid pipe)
sensor error
2 times/8 sec.
37
Vent-pipe sensor error
4 times/8 sec.
39
Others
Power cut for current protection
ON
1 time/8 sec.
42
Failure of outdoor unit
2 times/8 sec.
59
Current safety
3 times/8 sec.
58
Failure of power module
4 times/8 sec.
51
Compressor over heat protection
5 times/8 sec.
36
Serial signal transmission error
6 times/8 sec.
05
Outdoor fan motor error
7 times/8 sec.
48
Cool room high pressure protection
control
Continuous
flashing
35
Controllable silicon voltage error
5 times/8 sec.
ON
47
Cooling circulation system protection
7 times/8 sec.
57
Locked-rotor/rotor lock
2 times/8 sec.
2 times/8 sec.
60
The air conditioner indicates the error of the indoor and outdoor sensors (thermistors) only when it is
in the stop mode. Error indication is removed after restart.
1.2 Model identification
For example:
R410A Refrigerant used
Master pattern change code
Master pattern
Capacity
Wall mounted type (C is the code for outdoor unit.)
Split type room air conditioner

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2 MODEL SELECTION
2.1 Model function
2.1.1 Model: SRK20MA–S (Indoor unit)
SRC20MA–S (Outdoor unit)
Item
Unit
Indoor unit SRK20MA–S
Outdoor unit SRC20MA–S
Net weight
kg
10
32
Machine
dimension
mm
798×230×294
780×290×540
Package
dimension
Length×
Width ×Height
850×365×310
920×380×590
Color
White
Ash-colored
Fan
Through-flow type, AS resin +
glass fiber
Axial flow type, AS resin + glass
fiber (embedded damping spindle
sleeve)
Air flow
m3/h
600
1800
Noise in cool
room
dB(A)
Hi/Me/Lo: 37/27/21(completely
mute, SPL)
43(completely mute, SPL)
Noise in warm
room
dB(A)
Hi/Me/Lo: 37/28/24(completely
mute, SPL)
45(completely mute, SPL)
Fan motor
Nominal value
33W, DC motor, insulation grade E
24W, DC motor, insulation grade E
Power of motor
W (reference
value)
19
20
Power of electric
control
W (reference
value)
2
7.5
Power supply and
power cord
Single-phase, 220V, 50Hz and 3-core, 1.0mm2, 250V, 10A, 2m, w/o plug
Heat exchanger
Spiral, hydrophilic, 4-folded,
15-section, 2-row, 528-fin, 1-2
circuit
Spiral, hydrophilic, 20-section,
1-row, 621-fin, 2-1 circuit
Compressor
Nominal value
THACOM RM-B5077MDE2, 527W, DC frequency conversion
compressor, insulation grade E
Refrigerating
machine oil
ml
300, DIAMOND FREEZE MA68
Refrigerant
controller
Electronic expansion valve (Φ1.5mm) + hush pipe
Refrigerant
g
R-410A, 900g, addition/reduction not needed within the use range of 15m
Operating
pressure limit
Mpa
Max.: 4.15, Min.: 1.47
Air filters
Lysozyme filter + Antibacterial deodorizing filter + Mould-proof air filter
Accessories and
quantity
Indoor unit 1, mounting plate 1, tapping screw 5, battery 2, use and
installation manual 1, remote controller 1, filter components 2, outdoor unit
1, Drain elbow 1, Water shutoff plug 1
Operation control
devices
Wireless remote controller, electronic thermostat controlling room
temperature, microcomputer controlling defrosting
Safety devices
Serial signal protection, fan error protection, compressor over heat
protection, high voltage protection, over current protection, etc.
* The nominal values of “Noise in cool room” and “Noise in warm room” in the above table are tested in a dead
room.
Item
Unit
Rating cooling
Rating heating
Capacity
W
2000
2700
Power
W
450
600
Energy efficiency ratio
4.44
4.50
Energy efficiency grade
Grade A (European norm)
Note (1) The data are measured at the following conditions. The pipe length is 5m.
Item
Operation
Indoor air temperature
Outdoor air temperature
Standards
DB
WB
DB
WB
Cooling
27℃
19℃
35℃
24℃
Heating
20℃
—
7℃
6℃
Low temperature Heating
20℃
—
2℃
1℃
(2) The operation data are applied to the 220Vdistricts respectively.
(3) The refrigerant quantity to be charged includes the refrigerant in 15m connecting piping.
(Purging is not required even for the short piping.)

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2.1.2 Model: SRK25MA–S (Indoor unit)
SRC25MA–S (Outdoor unit)
Item
Unit
Indoor unit SRK25MA–S
Outdoor unit SRC25MA–S
Net weight
kg
10
32
Machine
dimension
mm
798×230×294
780×290×540
Package
dimension
Length×
Width ×Height
850×365×310
920×380×590
Color
White
Ash-colored
Fan
Through-flow type, AS resin +
glass fiber
Axial flow type, AS resin + glass
fiber (embedded damping spindle
sleeve)
Air flow
m3/h
600
1800
Noise in cool
room
dB(A)
Hi/Me/Lo: 37/27/22(completely
mute, SPL)
44(completely mute, SPL)
Noise in warm
room
dB(A)
Hi/Me/Lo: 38/29/23(completely
mute, SPL)
45(completely mute, SPL)
Fan motor
Nominal value
33W, DC motor, insulation grade E
24W, DC motor, insulation grade E
Power of motor
W (reference
value)
19
20
Power of electric
control
W (reference
value)
2
7.5
Power supply and
power cord
Single-phase, 220V, 50Hz and 3-core, 1.0mm2, 250V, 10A, 2m, w/o plug
Heat exchanger
Spiral, hydrophilic, 4-folded,
15-section, 2-row, 528-fin, 1-2
circuit
Spiral, hydrophilic, 20-section,
1-row, 621-fin, 2-1 circuit
Compressor
Nominal value
THACOM RM - B5077MDE2, 527W, DC frequency conversion
compressor, insulation grade E
Refrigerating
machine oil
ml
300, DIAMOND FREEZE MA68
Refrigerant
controller
Electronic expansion valve (Φ1.5mm) + hush pipe
Refrigerant
g
R-410A, 900g, addition/reduction not needed within the use range of 15m
Operating
pressure limit
Mpa
Max.: 4.15, Min.: 1.47
Air filters
Lysozyme filter + Antibacterial deodorizing filter + Mould-proof air filter
Accessories and
quantity
Indoor unit 1, mounting plate 1, tapping screw 5, battery 2, use and
installation manual 1, remote controller 1, filter components 2, outdoor unit
1, water elbow 1, Water shutoff plug 1
Operation control
devices
Wireless remote controller, electronic thermostat controlling room
temperature, microcomputer controlling defrosting
Safety devices
Serial signal protection, fan error protection, compressor over heat
protection, high voltage protection, over current protection, etc.
* The nominal values of “Noise in cool room” and “Noise in warm room” in the above table are tested in a dead
room.
Item
Unit
Rating cooling
Rating heating
Capacity
W
2500
3200
Power
W
680
790
Energy efficiency ratio
3.68
4.05
Energy efficiency grade
Grade A (European norm)
Note (1) The data are measured at the following conditions. The pipe length is 5m.
Item
Operation
Indoor air temperature
Outdoor air temperature
Standards
DB
WB
DB
WB
Cooling
27℃
19℃
35℃
24℃
Heating
20℃
—
7℃
6℃
Low temperature Heating
20℃
—
2℃
1℃
(2) The operation data are applied to the 220Vdistricts respectively.
(3) The refrigerant quantity to be charged includes the refrigerant in 15m connecting piping.
(Purging is not required even for the short piping.)

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2.1.2 Model: SRK35MA–S (Indoor unit)
SRC35MA–S (Outdoor unit)
Item
Unit
Indoor unit SRK35MA–S
Outdoor unit SRC35MA–S
Net weight
kg
10.5
35
Machine
dimension
mm
798×230×294
780×290×540
Package
dimension
Length×
Width ×Height
850×365×310
920×380×590
Color
White
Ash-colored
Fan
Through-flow type, AS resin +
glass fiber
Axial flow type, AS resin + glass
fiber (embedded damping spindle
sleeve)
Air flow
m3/h
600
1870
Noise in cool
room
dB(A)
Hi/Me/Lo: 39/31/23(completely
mute, SPL)
46(completely mute, SPL)
Noise in warm
room
dB(A)
Hi/Me/Lo: 41/34/23(completely
mute, SPL)
50(completely mute, SPL)
Fan motor
Nominal value
33W, DC motor, insulation grade E
24W, DC motor, insulation grade E
Power of motor
W (reference
value)
19
20
Power of electric
control
W (reference
value)
2
7.5
Power supply and
power cord
Single-phase, 220V, 50Hz and 3-core, 1.0mm2, 250V, 10A, 2m, w/o plug
Heat exchanger
Parent: Spiral, hydrophilic,
4-folded, 15-section, 2-row,
528-fin, Pf1.2
Child: Spiral, hydrophilic,
4-section, 1-row, 452-fin, Pf1.4
Spiral, hydrophilic, 20-section,
2-row, 1221-fin, 2-1 circuit, Pf1.4
Compressor
Nominal value
THACOM RM - B5077MDE2, 527W, DC frequency conversion
compressor, insulation grade E
Refrigerating
machine oil
ml
300, DIAMOND FREEZE MA68
Refrigerant
controller
Electronic expansion valve (Φ1.5mm) + hush pipe
Refrigerant
g
R-410A, 900g, addition/reduction not needed within the use range of 15m
Operating
pressure limit
Mpa
Max.: 4.15, Min.: 1.47
Air filters
Lysozyme filter + Antibacterial deodorizing filter + Mould-proof air filter
Accessories and
quantity
Indoor unit 1, mounting plate 1, tapping screw 5, battery 2, use and
installation manual 1, remote controller 1, filter components 2, outdoor unit
1, Drain elbow 1, Water shutoff plug 1
Operation control
devices
Wireless remote controller, electronic thermostat controlling room
temperature, microcomputer controlling defrosting
Safety devices
Serial signal protection, fan error protection, compressor over heat
protection, high voltage protection, over current protection, etc.
* The nominal values of “Noise in cool room” and “Noise in warm room” in the above table are tested in a dead
room.
Item
Unit
Rating cooling
Rating heating
Capacity
W
3500
4000
Power
W
960
1100
Energy efficiency ratio
3.65
3.64
Energy efficiency grade
Grade A (European norm)
Note (1) The data are measured at the following conditions. The pipe length is 5m.
Item
Operation
Indoor air temperature
Outdoor air temperature
Standards
DB
WB
DB
WB
Cooling
27℃
19℃
35℃
24℃
Heating
20℃
—
7℃
6℃
Low temperature Heating
20℃
—
2℃
1℃
(2) The operation data are applied to the 220Vdistricts respectively.
(3) The refrigerant quantity to be charged includes the refrigerant in 15m connecting piping.
(Purging is not required even for the short piping.)

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2.1.2 Model: SRK50MA–S (Indoor unit)
SRC50MA–S (Outdoor unit)
Item
Unit
Indoor unit SRK50MA–S
Outdoor unit SRC50MA–S
Net weight
kg
10.5
43
Machine
dimension
mm
798×230×294
850×290×640
Package
dimension
Length×
Width ×Height
850×365×310
990×395×700
Color
White
Ash-colored
Fan
Through-flow type, AS resin +
glass fiber
Axial flow type, AS resin + glass
fiber (embedded damping spindle
sleeve)
Air flow
m3/h
720
2400
Noise in cool
room
dB(A)
Hi/Me/Lo: 44/34/25(completely
mute, SPL)
50(completely mute, SPL)
Noise in warm
room
dB(A)
Hi/Me/Lo: 48/34/25(completely
mute, SPL)
50(completely mute, SPL)
Fan motor
Nominal value
33W, DC motor, insulation grade E
24W, DC motor, insulation grade E
Power of motor
W (reference
value)
19
20
Power of electric
control
W (reference
value)
2
7.5
Power supply and
power cord
Single-phase, 220V, 50Hz and 3-core, 1.5mm2, 250V, 16A, 2m, w/o plug
Heat exchanger
Parent: Spiral, hydrophilic,
4-folded, 15-section, 2-row,
528-fin, Pf1.2
Child: Spiral, hydrophilic,
4-section, 1-row, 452-fin, Pf1.4
Spiral, hydrophilic, 24-section,
2-row, 1334-fin, 4-1 circuit, Pf1.2
Compressor
Nominal value
THACOM RM - B5077MDE2, 527W, DC frequency conversion
compressor, insulation grade E
Refrigerating
machine oil
ml
300, DIAMOND FREEZE MA68
Refrigerant
controller
Electronic expansion valve (Φ1.5mm) + hush pipe
Refrigerant
g
R-410A, 1250g, addition/reduction not needed within the use range of 15m
Operating
pressure limit
Mpa
Max.: 4.15, Min.: 1.47
Air filters
Lysozyme filter + Antibacterial deodorizing filter + Mould-proof air filter
Accessories and
quantity
Indoor unit 1, mounting plate 1, tapping screw 5, battery 2, use and
installation manual 1, remote controller 1, filter components 2, outdoor unit
1, Drain elbow 1, Water shutoff plug 1
Operation control
devices
Wireless remote controller, electronic thermostat controlling room
temperature, microcomputer controlling defrosting
Safety devices
Serial signal protection, fan error protection, compressor over heat
protection, high voltage protection, over current protection, etc.
* The nominal values of “Noise in cool room” and “Noise in warm room” in the above table are tested in a dead
room.
Item
Unit
Rating cooling
Rating heating
Capacity
W
5000
5800
Power
W
1560
1600
Energy efficiency ratio
3.21
3.63
Energy efficiency grade
Grade A (European norm)
Note (1) The data are measured at the following conditions. The pipe length is 5m.
Item
Operation
Indoor air temperature
Outdoor air temperature
Standards
DB
WB
DB
WB
Cooling
27℃
19℃
35℃
24℃
Heating
20℃
—
7℃
6℃
Low temperature Heating
20℃
—
2℃
1℃
(2) The operation data are applied to the 220Vdistricts respectively.
(3) The refrigerant quantity to be charged includes the refrigerant in 15m connecting piping.
(Purging is not required even for the short piping.)

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2.2 Range of usage
Please use the air conditioners within the following range of usage, otherwise the protector will be
triggered.
Cooling Operation
Heating Operation
Outdoor temperature
About 18℃~43℃
About -15~24℃
Indoor temperature
About18℃~32℃
About below 30℃
Indoor humidity
About below 80%
20~50 Models
Max. piping one-way length
Within 15 m
Vertical height difference
Within 5 m
Additional R410A Refrigerant
Not required
Voltage
Rating ±10%
Starting voltage
At least 85% of rating
Switching frequency
Max. 10 times per hour
Time interval between stop and start
Min. 3 min
2.3 Outline drawing
(1) Indoor unit: MA-S Series Unit: mm

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