Mitsubishi Heavy Industries SRK20HD-S, SRK28HD-S, SRK28CD-S, SRK40CD-S, SRK40HD-S Technical Manual

-

3

-

WALL MOUNTED TYPE
ROOM AIR-CONDITIONER

(Split system, air to air heat pump type)
SRK20HD-S, SRK28HD-S, SRK40HD-S

(Split system, air cooled cooling only type)
SRK20CD-S, SRK28CD-S, SRK40CD-S

TECHNICAL MANUAL

Collection data

Manual No. ’04

.

SRK-T

.

040

-

1

-

CONTENTS

1. GENERAL INFORMATION.............................................................................. 1

1.1 Specific features ....................................................................................... 1

1.2 How to read the model name................................................................... 1

2. SELECTION DATA........................................................................................... 2

2.1 Specifications ........................................................................................... 2

2.2 Range of usage & limitations .................................................................. 8

2.3 Exterior dimensions ................................................................................. 8

2.4 Piping system ........................................................................................... 10

2.5 Selection chart .......................................................................................... 11

3. ELECTRICAL DATA ........................................................................................ 12

3.1 Electrical wiring ........................................................................................ 12

4. OUTLINE OF OPERATION CONTROL BY MICROCOMPUTER ................... 14

4.1 Operation control function by remote control switch........................... 14

4.2 Back-up switch ......................................................................................... 15

4.3 Power blackout auto restart function...................................................... 15

4.4 Flap control ............................................................................................... 16

4.5 Comfortable timer setting ........................................................................ 16

4.6 Outline of heating operation.................................................................... 17

4.7 Outline of cooling operation.................................................................... 20

4.8 Outline of dehumidifying operation ........................................................ 21

4.9 Automatic operation................................................................................. 22

4.10 Outline of fan operation ........................................................................... 22

4.11 Protective control function ...................................................................... 23

5. APPLICATION DATA....................................................................................... 25

5.1 Selection of location for installation....................................................... 26

5.2 Installation of indoor unit......................................................................... 27

5.3 Installation of outdoor unit ...................................................................... 29

5.4 Refrigerant piping..................................................................................... 29

5.5 T est run...................................................................................................... 31

5.6 Precautions for wireless remote controller installation and

operation ................................................................................................... 32

6. MAINTENANCE DATA .................................................................................... 33

6.1 Trouble shooting....................................................................................... 33

6.2 Servicing.................................................................................................... 38

-

1

-

Serial signal transmission error

1 GENERAL INFORMATION

1.1 Specific features

The “Mitsubishi Daiya” room air-conditioner: SRK series are of split and wall mounted type and the unit consists of indoor unit and
outdoor unit with refrigerant precharged in factory. The indoor unit is composed of room air cooling or heating equipment with opera­tion control switch and the outdoor unit is composed of condensing unit with compressor.

(1) Remote control flap

The flap can be automatically controlled by operating wireless remote controller.

¡ Air scroll: Flap operation is automatically control.
¡ Swing: This will swing the flap up and down.
¡ Memory flap: Once the flap position is set, the unit memorizes the position and continues to operate at the same position from

the next time.

(2) Automatic Operation

When the remote control switch is set on “auto( ) ”, it will either automatically decide operation mode such as cooling, heating
and thermal dry, or operate in the operation mode before it has been turned to automatic control.

(3) Self diagnosis function

¡ We are constantly trying to do better service to our customers by installing such judges that show abnormality of operation as

follows.

1.2 How to read the model name

Example : SR K 40 H D - S

Room temperature thermistor error

Indoor fan motor error

Heat exchanger thermistor error

2 time flash

6 time flash

TIMER lamp

ON

1 time flash

Outdoor unit heat exchanger
thermistor error

Discharge pipe thermistor error

Outdoor temperature thermistor
error

2 time flash

4 time flash

RUN lamp
keeps flashing

1 time flash

OFF

OFF

OFF

Outdoor unit error

Compressor overheat

Current cut

2 time flash

5 time flash

RUN lamp

ON

1 time flash

2 time flash

5 time flash

1 time flash

6 time flash 6 time flash

RUN lamp TIMER lamp Outdoor (LED)

R410A models
Series No.
H: Heat pump type
C: Cooling only type
Product capacity
Wall mounted type
Split type room air-conditioner

-

2

-

Item

Model

SRK20HD-S SRC20HD-S

Cooling capacity

(1)

W 2050

Heating capacity

(1)

W 2200

Power source 1 Phase, 220/230/240V, 50Hz

Cooling input kW 0.63
Running current (Cooling) A 3.1/3.0/2.9
Heating input kW 0.6
Running current (Heating) A 3.0/2.9/2.8
Inrush current A 18.9
COP Cooling: 3.21 Heating: 3.61

Cooling

sound level Hi 34, Me 28, Lo 26 46

Noise level

Power level

dB

52 60

Heating

sound level Hi 34, Me 31, Lo 27 46

Power level 52 60

Exterior dimensions

Height × Width × Depth

mm

250 × 815 × 249 540 × 720 × 290

Color Cool white Stucco white
Net weight kg 9.0 32
Refrigerant equipment

Compressor type & Q’ty

– RM-B5077MNE4 (Rotary type) × 1

Motor kW – 0.65

Starting method – Line starting
Heat exchanger Louver fins & inner grooved tubing
Refrigerant control Capillary tubes + Electronic expansion valve
Refrigerant

(3)

kg R410A 0.9 (Pre-Charged up to the piping length of 15m)
Refrigerant oil R 0.35 (MA68)
Deice control MC control

Air handling equipment

Fan type & Q’ty

Tangential fan × 1 Propeller fan × 1

Motor W 14 12

(Cooling) 7.5 26

Air flow (at High)

(Heating)

CMM

7.5 26

Air filter, Q’ty Polypropylene net (washable) × 2 –

Shock & vibration absorber – Cushion rubber (for compressor)
Electric heater ––
Operation control

Operation switch

Wireless-Remote controller –

Room temperature control MC. Thermostat –
Pilot lamp RUN (Green), TIMER (Yellow), HI POWER (Green), ECONO (Orange)

Safety equipment

O.D mm (in) Liquid line: φ6.35 (1/4″) Gas line: φ9.52 (3/8″)
Connecting method Flare connecting
Attached length of piping Liquid line: 0.4 m

Gas line : 0.33 m

–

Insulation Necessary (Both sides)
Drain hose Connectable
Power source cord 2.5 m (3 cores with Earth)

Size × Core number 1.5 mm2 × 4 cores (Including earth cable)

Connection wiring

Connecting method Terminal block (Screw fixing type)
Accessories (included) Mounting kit
Optional parts –

Notes (1) The data are measured at the following conditions.

2 SELECTION DATA

2.1 Specifications

Model SRK20HD-S (Indoor unit)

SRC20HD-S (Outdoor unit)

Item Indoor air temperature Outdoor air temperature

Standards

Operation DB WB DB WB

Cooling 27ºC19ºC35ºC24ºC ISO-T1, JIS C9612

Heating 20ºC – 7ºC6ºC ISO-T1, JIS C9612

(2) The operation data are applied to the 220/230/240V districts respectively.
(3) The refrigerant quantity to be charged includes the refrigerant in 15 m connecting piping.

(Purging is not required even in the short piping.)

Operation data

(1)

Refrigerant

piping

Compressor: Overheat protection, overcurrent protection, Serial signal error protection, Indoor fan mo­tor error protection, Frost protection

The piping length is 7.5m.

-

3

-

Item

Model

SRK28HD-S SRC28HD-S

Cooling capacity

(1)

W 2550

Heating capacity

(1)

W 2800

Power source 1 Phase, 220/230/240V, 50Hz

Cooling input kW 0.79
Running current (Cooling) A 3.9/3.7/3.5
Heating input kW 0.77
Running current (Heating) A 3.7/3.5/3.3
Inrush current A 17.2
COP Cooling: 3.21 Heating: 3.61

Cooling

sound level Hi 39, Me 33, Lo 30 46

Noise level

Power level

dB

55 60

Heating

sound level Hi 40, Me 33, Lo 29 46

Power level 56 60

Exterior dimensions

Height × Width × Depth

mm

250 × 815 × 249 540 × 720 × 290

Color Cool white Stucco white
Net weight kg 9.0 32
Refrigerant equipment

Compressor type & Q’ty

– 5PS102DAB [Rotary type] × 1

Motor kW – 0.7

Starting method – Line starting
Heat exchanger Louver fins & inner grooved tubing
Refrigerant control Capillary tubes + Electronic expansion valve
Refrigerant

(3)

kg R410A 0.9 (Pre-Charged up to the piping length of 15m)
Refrigerant oil R 0.35 (RB68A)
Deice control MC control

Air handling equipment

Fan type & Q’ty

Tangential fan × 1 Propeller fan × 1

Motor W 14 15

(Cooling) 8.0 30

Air flow (at High)

(Heating)

CMM

8.5 30

Air filter, Q’ty

Polypropylene net (washable) × 2

–

Shock & vibration absorber – Cushion rubber (for compressor)
Electric heater ––
Operation control

Operation switch

Wireless-Remote controller –

Room temperature control MC. Thermostat –
Pilot lamp RUN (Green), TIMER (Yellow), HI POWER (Green), ECONO (Orange)

Safety equipment

O.D mm (in) Liquid line: φ6.35 (1/4″) Gas line: φ9.52 (3/8″)
Connecting method Flare connecting
Attached length of piping Liquid line: 0.4 m

Gas line : 0.33 m

–

Insulation Necessary (Both sides)
Drain hose Connectable
Power source cord 2.5 m (3 cores with Earth)

Size × Core number 1.5 mm2 × 4 cores (Including earth cable)

Connection wiring

Connecting method Terminal block (Screw fixing type)
Accessories (included) Mounting kit
Optional parts –

Notes (1) The data are measured at the following conditions.

Model SRK28HD-S (Indoor unit)

SRC28HD-S (Outdoor unit)

Item Indoor air temperature Outdoor air temperature

Standards

Operation DB WB DB WB

Cooling 27ºC19ºC35ºC24ºC ISO-T1, JIS C9612

Heating 20ºC – 7ºC6ºC ISO-T1, JIS C9612

(2) The operation data are applied to the 220/230/240V districts respectively.
(3) The refrigerant quantity to be charged includes the refrigerant in 15 m connecting piping.

(Purging is not required even in the short piping.)

Operation data

(1)

Refrigerant

piping

Compressor: Overheat protection, overcurrent protection, Serial signal error protection, Indoor fan
motor error protection, Frost protection

The piping length is 7.5m.

-

4

-

Model SRK40HD-S (Indoor unit)

SRC40HD-S (Outdoor unit)

Item

Model

SRK40HD-S SRC40HD-S

Cooling capacity

(1)

W 3600

Heating capacity

(1)

W 4000

Power source 1 Phase, 220/230/240V, 50Hz

Cooling input kW 1.12
Running current (Cooling) A 5.3/5.1/4.9
Heating input kW 1.16
Running current (Heating) A 5.5/5.3/5.1
Inrush current A 25.2
COP Cooling: 3.21 Heating: 3.42

Cooling

sound level Hi 40, Me 38, Lo 34 49

Noise level

Power level

dB

56 63

Heating

sound level Hi 41, Me 38, Lo 34 50

Power level 57 64

Exterior dimensions

Height × Width × Depth

mm

250 × 815 × 249 640 × 850 × 290

Color Cool white Stucco white
Net weight kg 9.0 41
Refrigerant equipment

Compressor type & Q’ty

– 5KS150DBB [Rotary type] × 1

Motor kW – 1.1

Starting method – Line starting
Heat exchanger Louver fins & inner grooved tubing
Refrigerant control Capillary tubes + Electronic expansion valve
Refrigerant

(3)

kg R410A 1.17 (Pre-Charged up to the piping length of 15m)
Refrigerant oil R 0.43 (RB68A)
Deice control MC control

Air handling equipment

Fan type & Q’ty

Tangential fan × 1 Propeller fan × 1

Motor W 14 35

(Cooling) 9.0 38

Air flow (at High)

(Heating)

CMM

9.5 38

Air filter, Q’ty

Polypropylene net (washable) × 2

–

Shock & vibration absorber – Cushion rubber (for compressor)
Electric heater ––
Operation control

Operation switch

Wireless-Remote controller –

Room temperature control MC. Thermostat –
Pilot lamp RUN (Green), TIMER (Yellow), HI POWER (Green), ECONO (Orange)

Safety equipment

O.D mm (in) Liquid line: φ6.35 (1/4″) Gas line: φ12.7 (1/2″)
Connecting method Flare connecting
Attached length of piping Liquid line: 0.4 m

Gas line : 0.33 m

–

Insulation Necessary (Both sides)
Drain hose Connectable
Power source cord 2.5 m (3 cores with Earth)

Size × Core number 1.5 mm2 × 4 cores (Including earth cable)

Connection wiring

Connecting method Terminal block (Screw fixing type)
Accessories (included) Mounting kit
Optional parts –

Notes (1) The data are measured at the following conditions.

Item Indoor air temperature Outdoor air temperature

Standards

Operation DB WB DB WB

Cooling 27ºC19ºC35ºC24ºC ISO-T1, JIS C9612

Heating 20ºC – 7ºC6ºC ISO-T1, JIS C9612

(2) The operation data are applied to the 220/230/240V districts respectively.
(3) The refrigerant quantity to be charged includes the refrigerant in 15 m connecting piping.

(Purging is not required even in the short piping.)

Operation data

(1)

Refrigerant

piping

Compressor: Overheat protection, overcurrent protection, Serial signal error protection, Indoor fan
motor error protection, Frost protection

The piping length is 7.5m.

-

5

-

Item

Model

SRK20CD-S SRC20CD-S

Cooling capacity

(1)

W 2050

Power source 1 Phase, 220/230/240V, 50Hz

Cooling input kW 0.63
Running current (Cooling) A 3.1/3.0/2.9
Inrush current A 18.9
COP Cooling: 3.21

Cooling

sound level Hi 34, Me 28, Lo 26 46

Noise level

Power level

dB

52 60

Exterior dimensions

Height × Width × Depth

mm

250 × 815 × 249 540 × 720 × 290

Color Cool white Stucco white
Net weight kg 9.0 32
Refrigerant equipment

Compressor type & Q’ty

– RM-B5077MNE4 (Rotary type) × 1

Motor kW – 0.65

Starting method – Line starting
Heat exchanger Louver fins & inner grooved tubing
Refrigerant control Capillary tubes + Electronic expansion valve
Refrigerant

(3)

kg R410A 0.9 (Pre-Charged up to the piping length of 15m)
Refrigerant oil R 0.35 (MA68)
Deice control MC control

Air handling equipment

Fan type & Q’ty

Tangential fan × 1 Propeller fan × 1

Motor W 14 12

Air flow (at High) (Cooling) CMM 7.5 26
Air filter, Q’ty Polypropylene net (washable) × 2 –

Shock & vibration absorber – Cushion rubber (for compressor)
Electric heater ––
Operation control

Operation switch

Wireless-Remote controller –

Room temperature control MC. Thermostat –
Pilot lamp RUN (Green), TIMER (Yellow), HI POWER (Green), ECONO (Orange)

Safety equipment

O.D mm (in) Liquid line: φ6.35 (1/4″) Gas line: φ9.52 (3/8″)
Connecting method Flare connecting
Attached length of piping Liquid line: 0.4 m

Gas line : 0.33 m

–

Insulation Necessary (Both sides)
Drain hose Connectable
Power source cord 2.5 m (3 cores with Earth)

Size × Core number 1.5 mm2 × 4 cores (Including earth cable)

Connection wiring

Connecting method Terminal block (Screw fixing type)
Accessories (included) Mounting kit
Optional parts –

Notes (1) The data are measured at the following conditions.

Model SRK20CD-S (Indoor unit)

SRC20CD-S (Outdoor unit)

Item Indoor air temperature Outdoor air temperature

Standards

Operation DB WB DB WB

Cooling 27ºC19ºC35ºC24ºC ISO-T1, JIS C9612

(2) The operation data are applied to the 220/230/240V districts respectively.
(3) The refrigerant quantity to be charged includes the refrigerant in 15 m connecting piping.

(Purging is not required even in the short piping.)

Operation data

(1)

Refrigerant

piping

Compressor: Overheat protection, overcurrent protection, Serial signal error protection, Indoor fan mo­tor error protection, Frost protection

The piping length is 7.5m.

-

6

-

Item

Model

SRK28CD-S SRC28CD-S

Cooling capacity

(1)

W 2550

Power source 1 Phase, 220/230/240V, 50Hz

Cooling input kW 0.79
Running current (Cooling) A 3.9/3.7/3.5
Inrush current A 17.2
COP Cooling: 3.21

Cooling

sound level Hi 39, Me 33, Lo 30 46

Noise level

Power level

dB

55 60

Exterior dimensions

Height × Width × Depth

mm

250 × 815 × 249 540 × 720 × 290

Color Cool white Stucco white
Net weight kg 9.0 32
Refrigerant equipment

Compressor type & Q’ty

– 5PS102DAB [Rotary type] × 1

Motor kW – 0.7

Starting method – Line starting
Heat exchanger Louver fins & inner grooved tubing
Refrigerant control Capillary tubes + Electronic expansion valve
Refrigerant

(3)

kg R410A 0.9 (Pre-Charged up to the piping length of 15m)
Refrigerant oil R 0.35 (RB68A)
Deice control MC control

Air handling equipment

Fan type & Q’ty

Tangential fan × 1 Propeller fan × 1

Motor W 14 15
Air flow (at High) (Cooling) CMM 8.0 30
Air filter, Q’ty

Polypropylene net (washable) × 2

–

Shock & vibration absorber – Cushion rubber (for compressor)
Electric heater ––
Operation control

Operation switch

Wireless-Remote controller –

Room temperature control MC. Thermostat –
Pilot lamp RUN (Green), TIMER (Yellow), HI POWER (Green), ECONO (Orange)

Safety equipment

O.D mm (in) Liquid line: φ6.35 (1/4″) Gas line: φ9.52 (3/8″)

Connecting method Flare connecting

Attached length of piping Liquid line: 0.4 m

Gas line : 0.33 m

–

Insulation Necessary (Both sides)

Drain hose Connectable
Power source cord 2.5 m (3 cores with Earth)

Size × Core number 1.5 mm2 × 4 cores (Including earth cable)

Connection wiring

Connecting method Terminal block (Screw fixing type)
Accessories (included) Mounting kit
Optional parts –

Notes (1) The data are measured at the following conditions.

Model SRK28CD-S (Indoor unit)

SRC28CD-S (Outdoor unit)

Item Indoor air temperature Outdoor air temperature

Standards

Operation DB WB DB WB

Cooling 27ºC19ºC35ºC24ºC ISO-T1, JIS C9612

(2) The operation data are applied to the 220/230/240V districts respectively.
(3) The refrigerant quantity to be charged includes the refrigerant in 15 m connecting piping.

(Purging is not required even in the short piping.)

Operation data

(1)

Refrigerant

piping

Compressor: Overheat protection, overcurrent protection, Serial signal error protection, Indoor fan
motor error protection, Frost protection

The piping length is 7.5m.

-

7

-

Item

Model

SRK40CD-S SRC40CD-S

Cooling capacity

(1)

W 3600

Power source 1 Phase, 220/230/240V, 50Hz

Cooling input kW 1.12
Running current (Cooling) A 5.3/5.1/4.9
Inrush current A 25.2
COP Cooling: 3.21

Cooling

sound level Hi 40, Me 38, Lo 34 49

Noise level

Power level

dB

56 63

Exterior dimensions

Height × Width × Depth

mm

250 × 815 × 249 640 × 850 × 290

Color Cool white Stucco white
Net weight kg 9.0 41
Refrigerant equipment

Compressor type & Q’ty

– 5KS150DBB [Rotary type] × 1

Motor kW – 1.1

Starting method – Line starting
Heat exchanger Louver fins & inner grooved tubing
Refrigerant control Capillary tubes + Electronic expansion valve
Refrigerant

(3)

kg R410A 1.17 (Pre-Charged up to the piping length of 15m)
Refrigerant oil R 0.43 (RB68A)
Deice control MC control

Air handling equipment

Fan type & Q’ty

Tangential fan × 1 Propeller fan × 1

Motor W 14 35
Air flow (at High) (Cooling) CMM 9.0 38
Air filter, Q’ty

Polypropylene net (washable) × 2

–

Shock & vibration absorber – Cushion rubber (for compressor)
Electric heater ––
Operation control

Operation switch

Wireless-Remote controller –

Room temperature control MC. Thermostat –
Pilot lamp RUN (Green), TIMER (Yellow), HI POWER (Green), ECONO (Orange)

Safety equipment

O.D mm (in) Liquid line: φ6.35 (1/4″) Gas line: φ12.7 (1/2″)

Connecting method Flare connecting

Attached length of piping Liquid line: 0.4 m

Gas line : 0.33 m

–

Insulation Necessary (Both sides)

Drain hose Connectable
Power source cord 2.5 m (3 cores with Earth)

Size × Core number 1.5 mm2 × 4 cores (Including earth cable)

Connection wiring

Connecting method Terminal block (Screw fixing type)
Accessories (included) Mounting kit
Optional parts –

Notes (1) The data are measured at the following conditions.

Model SRK40CD-S (Indoor unit)

SRC40CD-S (Outdoor unit)

Item Indoor air temperature Outdoor air temperature

Standards

Operation DB WB DB WB

Cooling 27ºC19ºC35ºC24ºC ISO-T1, JIS C9612

(2) The operation data are applied to the 220/230/240V districts respectively.
(3) The refrigerant quantity to be charged includes the refrigerant in 15 m connecting piping.

(Purging is not required even in the short piping.)

Operation data

(1)

Refrigerant

piping

Compressor: Overheat protection, overcurrent protection, Serial signal error protection, Indoor fan
motor error protection, Frost protection

The piping length is 7.5m.

-

8

-

2.2 Range of usage & limitations

2.3 Exterior dimensions

Indoor return air temperature
(Upper, lower limits)

Refrigerant line (one way) length Max. 15m

All models

Refer to the selection chart

Power source voltage Rating ± 10%
Voltage at starting Min. 85% of rating
Frequency of ON-OFF cycle Max. 10 times/h
ON and OFF interval Max. 3 minutes

Outdoor air temperature
(Upper, lower limits)

Vertical height difference between
outdoor unit and indoor unit

Max. 10m (Outdoor unit is higher)
Max. 10m (Outdoor unit is lower)

Item

Models

(1) Indoor unit
Models All models

VIEW A

117.5

580 117.5

148.5

216.5216.5

8.2

44.5

236.1

5.7

450

450

67.5

42.7

47.2

175

44.5

216.5216.5

148.5

53.5

Piping for Gas

Drain hose 540 (ø16)

Piping for Liquid 465.1 (ø6.35)

Piping hole (ø65)

Piping hole (ø65)

( )

20.28: ø9.52
40: ø12.7

397.1

45

14.5

60

788

5

60

45

815

A

250

Unit: mm

Piping hole right(left)

Terminal block

9

60

45

3

249

-

9

-

(2) Outdoor unit
Models SRC20HD-S, 28HD-S, 20CD-S, 28CD-S

Drain hole

286.4
12

50

290

49.6

43.5

850

203.1

510 136.9

476

Elogated hole
(2-12x16)

314

12

328

Terminal block

Service valve (Liquide)
ø6.35 (1/4'')

Service valve (Gas)
ø12.7 (1/2'')

Ground
terminal

124

34.6

20˚

20˚

42.7

100.3

15

640

14

Models SRC40HD-S, 40CD-S

Unit: mm

290

540

14.4

47.4 42.6

264.5

71

404.5
510

720

17.8

Drain holes

50

12

39.7

99.9

340

312.5

13.5

14

139

2-16x12

61.9

139.3 33.3
Flare connecting ø6.35 (1/4")

Service valve (Liquid)

40

°

40

°

Flare connecting ø9.52 (3/8")

Service valve (Gas)

Terminal block

-

10

-

2.4 Piping system

Models SRK20HD-S, 28HD-S, 40HD-S

Models SRK20CD-S, 28CD-S

Model SRK40CD-S

Outdoor unitIndoor unit

Heat
exchanger

Room temp.
thermistor

Heat
exchanger

Flare connecting

Heat
exchanger
thermistor

Piping
(Liquid)
ø6.35

Check joint

4 way valve

Service valve (Liquid)

Flare connecting

Discharge temp.
thermistor

Cooling cycle
Heating cycle

Outdoor air
temp. thermistor

Heat exchanger
thermistor

Compressor

Capillary tube

Strainer

Accumulator

Service valve
(Gas)

Capillary tube

Electronic
expansion valve

( )

Piping

(Gas)
20, 28 : ø9.52
40 : ø12.7

Outdoor unitIndoor unit

Room temp.
thermistor

Heat
exchanger

Flare connecting

Heat
exchanger
thermistor

Piping
(Liquid)
ø6.35

Check joint

Service valve (Liquid)

Flare connecting

Discharge temp.
thermistor

Cooling cycle

Outdoor air
temp. thermistor

Heat
exchanger

Heat exchanger
thermistor

Compressor

Capillary tube

Strainer

Accumulator

Service valve
(Gas)

Capillary tube

Electronic
expansion valve

Piping
(Gas)
ø9.52

Outdoor unitIndoor unit

Room temp.
thermistor

Heat
exchanger

Flare connecting

Heat
exchanger
thermistor

Piping
(Liquid)
ø6.35

Check joint

Service valve (Liquid)

Flare connecting

Discharge temp.
thermistor

Cooling cycle

Outdoor air
temp. thermistor

Heat
exchanger

Heat exchanger
thermistor

Compressor

Capillary tube

Accumulator

Service valve
(Gas)

Electronic
expansion valve

Piping
(Gas)
ø12.7

-

11

-

2.5 Selection chart

Correct the cooling and heating capacity in accordance with the conditions as follows. The net cooling and heating capacity can be
obtained in the following way.

Net capacity = Capacity shown on specification ✕ Correction factors as follows.
(1) Coefficient of cooling and heating capacity in relation to temperatures

(2) Correction of cooling and heating capacity in relation to one way length of refrigerant piping

It is necessary to correct the cooling and heating capacity in relation to the one way piping length between the indoor and outdoor
units.

(3) Correction relative to frosting on outdoor heat exchanger during heating

In additions to the foregoing corrections (1), (2) the heating capacity needs to be adjusted also with respect to the frosting on the
outdoor heat exchanger.

How to obtain the cooling and heating capacity

Example : The net cooling capacity of the model SRK40HD-S with the piping length of 15m, indoor wet-bulb temperature at 19.0˚C
and outdoor dry-bulb temperature 35˚C is Net cooling capacity = 3600 ✕ 0.975 ✕ 1.0 = 3510 w

SRK40HD-S Length 15m

Factor by air
temperatures

15

ISO-T1 Standard ConditionOutdoor air W.B. temperature °C W.B.

010-10 -5 5

14 16 18 20 22

15

10

27
25

20
15

20

25

30

35

40

0.6

0.7

0.8

0.9

1.0

1.1

1.2

1.3

43

24

20

ISO-T1 Standard ConditionIndoor air W.B. temperature °C W.B.

Heating

Cooling

Applicable range

Coefficient of cooling &

Heating capacity in

relation to temperature

Cooling operation

Outdoor air D.B.

temperature

°C D.B.

Heating operation

Indoor air D.B.

temperature

°C D.B.

Piping length [m]

Cooling
Heating

7

1.0

1.0

10

0.99

1.0

15

0.975

1.0

Air inlet temperature of

outdoor unit in ˚C WB

Adjustment coefficient

-10

0.95-90.94-70.93-50.91-30.88-10.8610.8730.9251.00