Toshiba RAS-M24N3KV2-E Service Manual

SERVICE MANUAL

AIR-CONDITIONER

SPLIT TYPE

Indoor Unit

FILE NO. SVM-12087

<High Wall, Heat Pump Type>

RAS-M24N3KV2-E

R410A

February, 2013

FILE NO. SVM-12087

CONTENTS

1. SAFETY PRECAUTIONS .......................................................................... 2

2. SPECIFICATIONS...................................................................................... 4

3. REFRIGERANT R410A ............................................................................. 5

4. CONSTRUCTION VIEWS ........................................................................ 13

5. WIRING DIAGRAM .................................................................................. 14

6. SPECIFICATIONS OF ELECTRICAL PARTS ........................................ 15

7. REFRIGERANT CYCLE DIAGRAM ........................................................ 16

8. CONTROL BLOCK DIAGRAM ................................................................ 17

9. OPERATION DESCRIPTION ................................................................... 18

10. INSTALLATION PROCEDURE ................................................................ 38

11. HOW TO DIAGNOSE THE TROUBLE ...................................................... 50

12. HOW TO REPLACE THE MAIN PARTS ................................................... 67

13. EXPLODED VIEWS AND PARTS LIST ................................................... 74

– 1 –

13-1. Indoor Unit

FILE NO. SVM-12087

13. EXPLODED VIEWS AND PARTS LIST

Location Part Location Part

No. No. No. No.

201 43T21407 MOTOR FAN 222 43T39020 BAND, MOTOR, LEFT

202 43T22312 BEARING ASSY, MOLD 223 43T39023 BAND,MOTOR, RIGHT DOWN

203 43T70313 HOSE, DRAIN 224 43T39022 BAND, MOTOR, RIGHT UP

204 43T20016 FAN, ASSY, CROSS FLOW 225 43T09040 LOUVER, HORIZONTAL

205 43T49010 PIPE, SHIELD 226 43T03384 BODY ASSY, BACK

206 43T83305 HOLDER, REMOTE CONTROL 228 43T09471 GRILLE OF AIR INLET ASSY

207 43T82008 PLATE, INSTALLATION 229 43T80331 FILTER-AIR

209 43T19333 HOLDER, SENSOR 230 43T00594 FRONT PANEL ASSY

210 43T49043 HOLDER, PIPE 232 43T62031 COVER, TERMINAL

212 43T39021 BASE, BEARING 235 43T44031 EVAPORATOR ASSY

218 43T79313 CAP, DRAIN 238 43T66317 WIRELESS REMOTE CONTROLLER

Description Description

– 74 –

FILE NO. SVM-12087

1. SAFETY PRECAUTIONS

For general public use

Power supply cord of parts of appliance for outdoor use shall be at least polychloroprene sheathed flexible cord
(design H07RN-F) or cord designation 60245 IEC66. (Shall be installed in accordance with national wiring regulations.)

• Read this “SAFETY PRECAUTIONS” carefully before servicing.

• The precautions described below include the important items regarding safety. Observe them without fail.

• After the servicing work, perform a trial operation to check for any problem.

• Turn off the main power supply switch (or breaker) before the unit maintenance.

CAUTION

New Refrigerant Air Conditioner Installation

• THIS AIR CONDITIONER ADOPTS THE NEW HFC REFRIGERANT (R410A) WHICH DOES NOT
DESTROY OZONE LAYER.

R410A refrigerant is apt to be affected by impurities such as water, oxidizing membrane, and oils because
the working pressure of R410A refrigerant is approx. 1.6 times of refrigerant R22. Accompanied with the
adoption of the new refrigerant, the refrigeration machine oil has also been changed. Therefore, during
installation work, be sure that water, dust, former refrigerant, or refrigeration machine oil does not enter
into the new type refrigerant R410A air conditioner circuit.

To prevent mixing of refrigerant or refrigerating machine oil, the sizes of connecting sections of charging
port on main unit and installation tools are different from those used for the conventional refrigerant units.

Accordingly, special tools are required for the new refrigerant (R410A) units. For connecting pipes, use new
and clean piping materials with high pressure fittings made for R410A only, so that water and/or dust does
not enter. Moreover, do not use the existing piping because there are some problems with pressure fittings
and possible impurities in existing piping.

CAUTION

TO DISCONNECT THE APPLIANCE FROM THE MAIN POWER SUPPLY

This appliance must be connected to the main power supply by a circuit breaker or a switch with a contact
separation of at least 3 mm.

DANGER

• ASK AN AUTHORIZED DEALER OR QUALIFIED INSTALLATION PROFESSIONAL TO INSTALL/
MAINTAIN THE AIR CONDITIONER.

INAPPROPRIATE SERVICING MAY RESULT IN WATER LEAKAGE, ELECTRIC SHOCK OR FIRE.

• TURN OFF MAIN POWER SUPPLY BEFORE ATTEMPTING ANY ELECTRICAL WORK. MAKE SURE
ALL POWER SWITCHES ARE OFF. FAILURE TO DO SO MAY CAUSE ELECTRIC SHOCK.

DANGER: HIGH VOLTAGE

The high voltage circuit is incorporated.
Be careful to do the check service, as the electric shock may be caused in case of touching parts

on the P.C. board by hand.

• CORRECTLY CONNECT THE CONNECTING CABLE. IF THE CONNECTING CABLE IS INCOR­RECTLY CONNECTED, ELECTRIC PARTS MAY BE DAMAGED.

• CHECK THAT THE EARTH WIRE IS NOT BROKEN OR DISCONNECTED BEFORE SERVICE AND
INSTALLATION. FAILURE TO DO SO MAY CAUSE ELECTRIC SHOCK.

– 2 –

FILE NO. SVM-12087

• DO NOT INSTALL NEAR CONCENTRATIONS OF COMBUSTIBLE GAS OR GAS VAPORS. FAILURE
TO FOLLOW THIS INSTRUCTION CAN RESULT IN FIRE OR EXPLOSION.

• TO PREVENT THE INDOOR UNIT FROM OVERHEATING AND CAUSING A FIRE HAZARD, PLACE
THE UNIT WELL AWAY (MORE THAN 2 M) FROM HEAT SOURCES SUCH AS RADIATORS, HEAT
REGISTERS, FURNACE, STOVES, ETC.

• WHEN MOVING THE AIR CONDITIONER FOR INSTALLATION IN ANOTHER PLACE, BE VERY CARE­FUL NOT TO ALLOW THE SPECIFIED REFRIGERANT (R410A) TO BECOME MIXED WITH ANY
OTHER GASEOUS BODY INTO THE REFRIGERATION CIRCUIT. IF AIR OR ANY OTHER GAS IS
MIXED IN THE REFRIGERANT, THE GAS PRESSURE IN THE REFRIGERATION CIRCUIT WILL
BECOME ABNORMALLY HIGH AND IT MAY RESULT IN THE PIPE BURSTING AND POSSIBLE
PERSONNEL INJURIES.

• IN THE EVENT THAT THE REFRIGERANT GAS LEAKS OUT OF THE PIPE DURING THE SERVICE
WORK AND THE INSTALLATION WORK, IMMEDIATELY LET FRESH AIR INTO THE ROOM.
IF THE REFRIGERANT GAS IS HEATED, SUCH AS BY FIRE, GENERATION OF POISONOUS GAS
MAY RESULT.

WARNING

• Never modify this unit by removing any of the safety guards or bypass any of the safety interlock
switches.

• Do not install in a place which cannot bear the weight of the unit. Personal injury and property
damage can result if the unit falls.

• After the installation work, confirm that refrigerant gas does not leak.

If refrigerant gas leaks into the room and flows near a fire source, such as a cooking range, noxious gas
may generate.

• The electrical work must be performed by a qualified electrician in accordance with the Installa­tion Manual. Make sure the air conditioner uses an exclusive circuit.

An insufficient circuit capacity or inappropriate installation may cause fire.

• When wiring, use the specified cables and connect the terminals securely to prevent external
forces applied to the cable from affecting the terminals.

• Be sure to provide grounding.

Do not connect ground wires to gas pipes, water pipes, lightning rods or ground wires for telephone cables.

• Conform to the regulations of the local electric company when wiring the power supply.

Inappropriate grounding may cause electric shock.

CAUTION

• Exposure of unit to water or other moisture before installation may result in an electrical short.
Do not store in a wet basement or expose to rain or water.

• Do not install in a place that can increase the vibration of the unit. Do not install in a place that can
amplify the noise level of the unit or where noise or discharged air might disturb neighbors.

• To avoid personal injury, be careful when handling parts with sharp edges.

• Perform the specified installation work to guard against an earthquake.

If the air conditioner is not installed appropriately, accidents may occur due to the falling unit.

For Reference:

If a heating operation would be continuously performed for a long time under the condition that the outdoor
temperature is 0°C or lower, drainage of defrosted water may be difficult due to freezing of the bottom
plate, resulting in a trouble of the cabinet or fan.

It is recommended to procure an antifreeze heater locally for a safe installation of the air conditioner.
For details, contact the dealer.

– 3 –

2. SPECIFICATIONS

FILE NO. SVM-12087

Unit model Outdoor
Cooling capacity (kW)
Cooling capacity range (kW)
Heating capacity (kW)
Heating capacity range (kW)
Power supply
Electric Indoor Operation mode Cooling Heating
characteristic Running current (A) 0.38-0.35 0.38-0.35

Power consumption (W) 50 50
Power factor (%) 60 60

Outdoor Operation mode Cooling Heating

Running current (A)
Power consumption (W)
Power factor (%)

Starting current (A)
COP (Cooling/Heating)
Operating Indoor High (Cooling/Heating) (dB-A)
noise Medium (Cooling/Heating) (dB-A)

Low (Cooling/Heating) (dB-A)

Outdoor (Cooling/Heating) (dB-A)

Indoor unit Dimension High (mm)

Medium (mm)

Depth (mm)

Net weight (kg)
Fan motor output (W)
Air flow rate (Cooling/Heating)

Outdoor unit Dimension High (mm)

Medium (mm)

Depth (mm)

Net weight (kg)
Compressor Motor output (W)

Type

Model

Fan motor output (W)

Air flow rate (Cooling/Heating)
Piping Type
connection Indoor unit Liquid side (mm)

Gas side (mm)

Outdoor unit Liquid side (mm)

Gas side (mm)
Maximum length (m)
Maximum chargeless length (m)
Maximum height difference (m)

Refrigerant Name of refrigerant

Weight (kg)

Wiring Power supply
connection Interconnection
Usable temperature range Indoor (Cooling/Heating)

Outdoor (Cooling/Heating)

Accessory Indoor unit Installation plate

Wireless remote controller

Batteries

Remote controller holder

Toshiba New IAQ filter

Mounting screw

Remote controller holder

Pan head wood screw

Installation manual

Owner's manual
Outdoor unit Drain nipple

Water-proof rubber cap

(m3/min)

(m3/min)

(°C)
(°C)

RAS-M24N3KV2-E

*

*

*

*

1Ph/50Hz/220-240V, 1Ph/60Hz/220V

*

*

*

*
*

49/49
43/43
37/37

*

320

1050

228

13
30

18.9/19.2
*
*
*
*
*

*

*
*
*

Flare connection

6.35
12.7

*
*

*
*
*

R410A

*

3Wires:includes earth(Outdoor)

4Wires:includes earth

21-32/ 0-28

*
1
1
2
1
4

6(4x25L)

2(3.1Lx16L)

1
1
*
*

*1 Refer to Service manual of the multi outdoor unit to be combined.
The specifications may be subject to change without notice for purpose of improvement.

– 4 –

3. REFRIGERANT R410A

FILE NO. SVM-12087

This air conditioner adopts the new refrigerant HFC
(R410A) which does not damage the ozone layer.

The working pressure of the new refrigerant R410A
is 1.6 times higher than conventional refrigerant
(R22). The refrigerating oil is also changed in
accordance with change of refrigerant, so be careful
that water, dust, and existing refrigerant or
refrigerating oil are not entered in the refrigerant
cycle of the air conditioner using the new refrigerant
during installation work or servicing time.

The next section describes the precautions for air
conditioner using the new refrigerant. Conforming
to contents of the next section together with the
general cautions included in this manual, perform
the correct and safe work.

3-1. Safety During Installation/Servicing

As R410A’s pressure is about 1.6 times higher than
that of R22, improper installation/servicing may
cause a serious trouble. By using tools and
materials exclusive for R410A, it is necessary to
carry out installation/servicing safely while taking
the following precautions into consideration.

1. Never use refrigerant other than R410A in an air
conditioner which is designed to operate with
R410A.

If other refrigerant than R410A is mixed,
pressure in the refrigeration cycle becomes
abnormally high, and it may cause personal
injury, etc. by a rupture.

2. Confirm the used refrigerant name, and use
tools and materials exclusive for the refrigerant
R410A.

The refrigerant name R410A is indicated on the
visible place of the outdoor unit of the air condi­tioner using R410A as refrigerant. To prevent
mischarging, the diameter of the service port
differs from that of R22.

3. If a refrigeration gas leakage occurs during
installation/servicing, be sure to ventilate fully.

If the refrigerant gas comes into contact with fire,
a poisonous gas may occur.

4. When installing or removing an air conditioner,
do not allow air or moisture to remain in the
refrigeration cycle. Otherwise, pressure in the
refrigeration cycle may become abnormally high
so that a rupture or personal injury may be
caused.

5. After completion of installation work, check to
make sure that there is no refrigeration gas
leakage.

If the refrigerant gas leaks into the room, coming
into contact with fire in the fan-driven heater,
space heater, etc., a poisonous gas may occur.

6. When an air conditioning system charged with a
large volume of refrigerant is installed in a small
room, it is necessary to exercise care so that,
even when refrigerant leaks, its concentration
does not exceed the marginal level.

If the refrigerant gas leakage occurs and its
concentration exceeds the marginal level, an
oxygen starvation accident may result.

7. Be sure to carry out installation or removal
according to the installation manual.

Improper installation may cause refrigeration
trouble, water leakage, electric shock, fire, etc.

8. Unauthorized modifications to the air conditioner
may be dangerous.

If a breakdown occurs please call a qualified air
conditioner technician or electrician.

Improper repair may result in water leakage,
electric shock and fire, etc.

3-2. Refrigerant Piping Installation

3-2-1. Piping Materials and Joints Used

For the refrigerant piping installation, copper pipes
and joints are mainly used.

Copper pipes and joints suitable for the refrigerant
must be chosen and installed.

Furthermore, it is necessary to use clean copper
pipes and joints whose interior surfaces are less
affected by contaminants.

1. Copper Pipes

It is necessary to use seamless copper pipes
which are made of either copper or copper alloy
and it is desirable that the amount of residual oil
is less than 40 mg/10 m.

Do not use copper pipes having a collapsed,
deformed or discolored portion
(especially on the interior surface).

Otherwise, the expansion valve or capillary tube
may become blocked with contaminants.

As an air conditioner using R410A incurs pres­sure higher than when using R22, it is necessary
to choose adequate materials.

Thicknesses of copper pipes used with R410A
are as shown in Table 3-2-1.

Never use copper pipes thinner than 0.8 mm
even when it is available on the market.

– 5 –

Table 3-2-1 Thicknesses of annealed copper pipes

Thickness (mm)

FILE NO. SVM-12087

Nominal diameter

1/4

3/8

1/2

5/8

Outer diameter (mm)

6.35

9.52

12.70

15.88

R410A R22

0.80 0.80

0.80 0.80

0.80 0.80

1.00 1.00

2. Joints

For copper pipes, flare joints or socket joints are used. Prior to use, be sure to remove all contaminants.
a) Flare Joints

Flare joints used to connect the copper pipes cannot be used for pipings whose outer diameter exceeds
20 mm. In such a case, socket joints can be used.

Sizes of flare pipe ends, flare joint ends and flare nuts are as shown in Tables 3-2-3 to 3-2-6 below.

b) Socket Joints

Socket joints are such that they are brazed for connections, and used mainly for thick pipings whose
diameter is larger than 20 mm.

Thicknesses of socket joints are as shown in Table 3-2-2.

Table 3-2-2 Minimum thicknesses of socket joints

Nominal diameter

1/4

3/8

1/2

5/8

Reference outer diameter of

copper pipe jointed (mm)

6.35

9.52

12.70

15.88

Minimum joint thickness

(mm)

0.50

0.60

0.70

0.80

3-2-2. Processing of Piping Materials

When performing the refrigerant piping installation, care should be taken to ensure that water or dust does not
enter the pipe interior, that no other oil than lubricating oils used in the installed air-water heat pump is used,
and that refrigerant does not leak.
When using lubricating oils in the piping processing, use such lubricating oils whose water content has been
removed. When stored, be sure to seal the container with an airtight cap or any other cover.

1. Flare processing procedures and precautions

a) Cutting the Pipe

By means of a pipe cutter, slowly cut the pipe so that it is not deformed.

b) Removing Burrs and Chips

If the flared section has chips or burrs, refrigerant leakage may occur.
Carefully remove all burrs and clean the cut surface before installation.

c) Insertion of Flare Nut

– 6 –

A

ØD

d) Flare Processing

Make certain that a clamp bar and copper
pipe have been cleaned.

By means of the clamp bar, perform the flare
processing correctly.

Use either a flare tool for R410A or conven­tional flare tool.

Flare processing dimensions differ according
to the type of flare tool.

When using a conventional flare tool, be sure
to secure “dimension A” by using a gauge for
size adjustment.

Table 3-2-3 Dimensions related to flare processing for R410A

FILE NO. SVM-12087

Fig. 3-2-1 Flare processing dimensions

Nominal

diameter

1/4 6.35 0.8

3/8 9.52 0.8

1/2 12.70 0.8

5/8 15.88 1.0

Nominal

diameter

1/4 6.35 0.8

3/8 9.52 0.8

Outer

diameter

(mm)

Table 3-2-4 Dimensions related to flare processing for R22

Outer

diameter

(mm)

Thickness

(mm)

Thickness

(mm)

Flare tool for R410A

clutch type

0 to 0.5

0 to 0.5

0 to 0.5

0 to 0.5

Flare tool for R22

clutch type

0 to 0.5

0 to 0.5

A (mm)

Conventional flare tool

Clutch type Wing nut type

1.0 to 1.5 1.5 to 2.0

1.0 to 1.5 1.5 to 2.0

1.0 to 1.5 2.0 to 2.5

1.0 to 1.5 2.0 to 2.5

A (mm)

Conventional flare tool

Clutch type Wing nut type

0.5 to 1.0 1.0 to 1.5

0.5 to 1.0 1.0 to 1.5

1/2 12.70 0.8

5/8 15.88 1.0

Table 3-2-5 Flare and flare nut dimensions for R410A

Nominal Outer diameter Thickness

diameter (mm) (mm)

1/4 6.35 0.8

3/8 9.52 0.8

1/2 12.70 0.8

5/8 15.88 1.0

– 7 –

0 to 0.5

0 to 0.5

Dimension (mm)

ABCD

9.1 9.2 6.5 13

13.2 13.5 9.7 20

16.0 16.6 12.9 23

19.0 19.7 16.0 25

0.5 to 1.0 1.5 to 2.0

0.5 to 1.0 1.5 to 2.0

Flare nut width

(mm)

17

22

26

29

Table 3-2-6 Flare and flare nut dimensions for R22

FILE NO. SVM-12087

Nominal Outer diameter Thickness

diameter (mm) (mm)

1/4 6.35 0.8

3/8 9.52 0.8

1/2 12.70 0.8

5/8 15.88 1.0

3/4 19.05 1.0

45˚ to 46˚

B A

Dimension (mm)

ABCD

9.0 9.2 6.5 13

13.0 13.5 9.7 20

16.0 16.2 12.9 20

19.0 19.7 16.0 23

23.3 24.0 19.2 34

D

C

43˚ to 45˚

Flare nut width

(mm)

17

22

24

27

36

Fig. 3-2-2 Relations between flare nut and flare seal surface

2. Flare Connecting Procedures and Precautions

a) Make sure that the flare and union portions do not have any scar or dust, etc.
b) Correctly align the processed flare surface with the union axis.
c) Tighten the flare with designated torque by means of a torque wrench.

The tightening torque for R410A is the same as that for conventional R22.
Incidentally, when the torque is weak, the gas leakage may occur.

When it is strong, the flare nut may crack and may be made non-removable.
When choosing the tightening torque, comply with values designated by manufacturers.
Table 3-2-7 shows reference values.

NOTE :

When applying oil to the flare surface, be sure to use oil designated by the manufacturer.
If any other oil is used, the lubricating oils may deteriorate and cause the compressor to burn out.

Table 3-2-7 Tightening torque of flare for R410A [Reference values]

Nominal

diameter

Outer

diameter

(mm)

Tightening torque

N•m (kgf•cm)

1/4 6.35 14 to 18 (140 to 180)

torque wrenches available on the market

Tightening torque of

N•m (kgf•cm)

16 (160), 18 (180)

3/8 9.52 33 to 42 (330 to 420)

1/2 12.70 50 to 62 (500 to 620)

5/8 15.88 63 to 77 (630 to 770)

– 8 –

42 (420)

55 (550)

65 (650)

FILE NO. SVM-12087

3-3. Tools

3-3-1. Required Tools

The service port diameter of packed valve of the outdoor unit in the air-water heat pump using R410A is
changed to prevent mixing of other refrigerant.
To reinforce the pressure-resisting strength, flare processing dimensions and opposite side dimension of flare
nut (For Ø12.7 copper pipe) of the refrigerant piping are lengthened.

The used refrigerating oil is changed, and mixing of oil may cause a trouble such as generation of sludge,
clogging of capillary, etc. Accordingly, the tools to be used are classified into the following three types.

1. Tools exclusive for R410A (Those which cannot be used for conventional refrigerant (R22))

2. Tools exclusive for R410A, but can be also used for conventional refrigerant (R22)

3. Tools commonly used for R410A and for conventional refrigerant (R22)
The table below shows the tools exclusive for R410A and their interchangeability.

Tools exclusive for R410A (The following tools for R410A are required.)

Tools whose specifications are changed for R410A and their interchangeability

No.

1

2

3

4

5

6

7

8

9

10

Used tool

Flare tool

Copper pipe gauge
for adjusting
projection margin

Torque wrench
(For Ø12.7)

Gauge manifold

Charge hose

Vacuum pump
adapter

Electronic balance for
refrigerant charging

Refrigerant cylinder

Leakage detector

Charging cylinder

Usage

Pipe flaring

Flaring by
conventional flare tool

Connection of flare nut

Evacuating, refrigerant
charge, run check, etc.

Vacuum evacuating

Refrigerant charge

Refrigerant charge

Gas leakage check

Refrigerant charge

air-water heat pump installation

R410A

Existence of Whether conventional
new equipment equipment can be
for R410A used

Ye s ∗ (Note 1)

Ye s ∗ (Note 1)

Ye s No

Ye s No

Ye s No

Ye s No

Ye s No

Ye s No

∗ (Note 2) No

Conventional air-water
heat pump installation

Whether new equipment
can be used with
conventional refrigerant

Ye s

∗ (Note 1)

No

No

Ye s

Ye s

No

Ye s

No

(Note 1) When flaring is carried out for R410A using the conventional flare tools, adjustment of projection

margin is necessary. For this adjustment, a copper pipe gauge, etc. are necessary.

(Note 2) Charging cylinder for R410A is being currently developed.

General tools (Conventional tools can be used.)

In addition to the above exclusive tools, the following equipments which serve also for R22 are neces­sary as the general tools.

1. Vacuum pump
Use vacuum pump by attaching
vacuum pump adapter.

2. Torque wrench (For Ø6.35, Ø9.52)

3. Pipe cutter

4. Reamer

5. Pipe bender

6. Level vial

7. Screwdriver (+, –)

8. Spanner or Monkey wrench

9. Hole core drill (Ø65)

10. Hexagon wrench
(Opposite side 4mm)

11. Tape measure

12. Metal saw

Also prepare the following equipments for other installation method and run check.

1. Clamp meter

2. Thermometer

3. Insulation resistance tester

4. Electroscope

– 9 –

FILE NO. SVM-12087

3-4. Recharging of Refrigerant

When it is necessary to recharge refrigerant, charge the specified amount of new refrigerant according to the
following steps.

Recover the refrigerant, and check no refrigerant
remains in the equipment.

Connect the charge hose to packed valve service
port at the outdoor unit’s gas side.

Connect the charge hose to the vacuum pump
adapter.

Open fully both packed valves at liquid and gas
sides.

When the compound gauge’s pointer has indicated
–0.1 Mpa (–76 cmHg), place the handle Low in the
fully closed position, and turn off the vacuum pump’s
power switch.

Keep the status as it is for 1 to 2 minutes, and ensure
that the compound gauge’s pointer does not return.

Set the refrigerant cylinder to the electronic balance,
connect the connecting hose to the cylinder and the
connecting port of the electronic balance, and charge
liquid refrigerant.

Place the handle of the gauge manifold Low in the
fully opened position, and turn on the vacuum pump’s
power switch. Then, evacuating the refrigerant in the
cycle.

(For refrigerant charging, see the figure below.)

1. Never charge refrigerant exceeding the specified amount.

2. If the specified amount of refrigerant cannot be charged, charge refrigerant bit by bit in COOL mode.

3. Do not carry out additional charging.
When additional charging is carried out if refrigerant leaks, the refrigerant composition changes in the

refrigeration cycle, that is characteristics of the air conditioner changes, refrigerant exceeding the
specified amount is charged, and working pressure in the refrigeration cycle becomes abnormally high
pressure, and may cause a rupture or personal injury.

(Indoor unit)

Opened

(Outdoor unit)

Refrigerant cylinder

(with siphon)

Check valve

Opened
Open/close
valve for charging

Electronic balance for refrigerant charging

Fig. 3-4-1 Configuration of refrigerant charging

Opened

Closed

Service port

– 10 –

FILE NO. SVM-12087

1. Be sure to make setting so that liquid can be charged.

2. When using a cylinder equipped with a siphon, liquid can be charged without turning it upside down.

It is necessary for charging refrigerant under condition of liquid because R410A is mixed type of refrigerant.
Accordingly, when charging refrigerant from the refrigerant cylinder to the equipment, charge it turning the
cylinder upside down if cylinder is not equipped with siphon.

[ Cylinder with siphon ] [ Cylinder without siphon ]

Gauge manifold

OUTDOOR unit

Refrigerant

cylinder

Gauge manifold

OUTDOOR unit

cylinder

Refrigerant

Electronic

balance

R410A refrigerant is HFC mixed refrigerant.
Therefore, if it is charged with gas, the composi­tion of the charged refrigerant changes and the
characteristics of the equipment varies.

3-5. Brazing of Pipes

3-5-1. Materials for Brazing

1. Silver brazing filler

Silver brazing filler is an alloy mainly composed
of silver and copper. It is used to join iron, copper
or copper alloy, and is relatively expensive
though it excels in solderability.

2. Phosphor bronze brazing filler

Phosphor bronze brazing filler is generally used
to join copper or copper alloy.

Electronic

balance

Siphon

Fig. 3-4-2

1. Phosphor bronze brazing filler tends to react
with sulfur and produce a fragile compound
water solution, which may cause a gas
leakage. Therefore, use any other type of
brazing filler at a hot spring resort, etc., and
coat the surface with a paint.

2. When performing brazing again at time of
servicing, use the same type of brazing filler.

3-5-2. Flux

3. Low temperature brazing filler

Low temperature brazing filler is generally called
solder, and is an alloy of tin and lead.
Since it is weak in adhesive strength, do not use
it for refrigerant pipes.

1. Reason why flux is necessary

• By removing the oxide film and any foreign
matter on the metal surface, it assists the flow
of brazing filler.

• In the brazing process, it prevents the metal
surface from being oxidized.

• By reducing the brazing filler’s surface tension,
the brazing filler adheres better to the treated
metal.

– 11 –

Nitrogen gas

cylinder

Pipe

Flow meter

M

Stop valve

From Nitrogen cylinder

Nitrogen gas

Rubber plug

2. Characteristics required for flux

• Activated temperature of flux coincides with
the brazing temperature.

• Due to a wide effective temperature range, flux
is hard to carbonize.

• It is easy to remove slag after brazing.

• The corrosive action to the treated metal and
brazing filler is minimum.

• It excels in coating performance and is harm­less to the human body.

As the flux works in a complicated manner as
described above, it is necessary to select an
adequate type of flux according to the type and
shape of treated metal, type of brazing filler and
brazing method, etc.

3. Types of flux

• Noncorrosive flux

Generally, it is a compound of borax and boric
acid.

It is effective in case where the brazing tem­perature is higher than 800°C.

• Activated flux

Most of fluxes generally used for silver brazing
are this type.

It features an increased oxide film removing
capability due to the addition of compounds
such as potassium fluoride, potassium chloride
and sodium fluoride to the borax-boric acid
compound.

4. Piping materials for brazing and used
brazing filler/flux

FILE NO. SVM-12087

3-5-3. Brazing

As brazing work requires sophisticated techniques,
experiences based upon a theoretical knowledge, it
must be performed by a person qualified.

In order to prevent the oxide film from occurring in
the pipe interior during brazing, it is effective to
proceed with brazing while letting dry Nitrogen gas
(N2) flow.

Never use gas other than Nitrogen gas.

1. Brazing method to prevent oxidation

1) Attach a reducing valve and a flow-meter to
the Nitrogen gas cylinder.

2) Use a copper pipe to direct the piping mate­rial, and attach a flow-meter to the cylinder.

3) Apply a seal onto the clearance between the
piping material and inserted copper pipe for
Nitrogen in order to prevent backflow of the
Nitrogen gas.

4) When the Nitrogen gas is flowing, be sure to
keep the piping end open.

5) Adjust the flow rate of Nitrogen gas so that it
is lower than 0.05 m
(0.2kgf/cm2) by means of the reducing valve.

6) After performing the steps above, keep the
Nitrogen gas flowing until the pipe cools down
to a certain extent (temperature at which
pipes are touchable with hands).

7) Remove the flux completely after brazing.

3

/Hr or 0.02 MPa

Piping material

Copper - Copper

1. Do not enter flux into the refrigeration cycle.

2. When chlorine contained in the flux remains

3. When adding water to the flux, use water

4. Remove the flux after brazing.

Copper - Iron

Iron - Iron

Used brazing filler

Phosphor copper

Silver

Silver

Used flux

Do not use

Paste flux

Vapor flux

within the pipe, the lubricating oil deterio­rates. Therefore, use a flux which does not
contain chlorine.

which does not contain chlorine
(e.g. distilled water or ion-exchange water).

Fig. 3-5-1

Prevention of oxidation during brazing

– 12 –

FILE NO. SVM-12087

Indoor Unit

Grille Inlet

Front Panel

73.5 7
50

Knock out system Knock out system

Heat exchanger

320

4. CONSTRUCTION VIEWS

Air Inlet

1050

Air filter

Air outlet

243

50

73.5
7

Drain hose (0.5m)

Connecting pipe (0.39m)

(Flare

50

72 78

132

525

Hanger Hanger

Connecting pipe (0.49m)

12.70)

85

Hanger

786

235

215 215

235

78 72

150 200 222 200 278

(Flare

23

50

Wireless remote controller

Remote controller holder

6.35)

For stud bold (
For stud bold (

57

63

6)
8~

172

18

149

17.5

10)

320

40

47

65

215.5

Hanger

262.5

Center line

262.5

Installation plate outline

– 13 –

Hanger

153.5

Outline of indoor unit

65

109

40

Indoor Unit

Outdoor Terminal Block

5. WIRING DIAGRAM

Indoor Terminal Block

1

1

BLK

2

2

WHI

3

3

RED

FILE NO. SVM-12087

GRN&YEL

Heat exchanger

SHEET METAL

CN01

3

(WHI)

3

Fuse F01

T3.15A 250VAC

1 1
2

2

Heat Exchanger Sensor

(TCJ)

Heat Exchanger Sensor

(TC)

Thermo Sensor

(TA)

CN63
(YEL)

2112

CN62
(BLU)

11
22

CN61
(WHI)

BLU

1

BLU

2

2

BLU

3

3

BLU

4

4

BLU

5

5

BLU

6

6

BLU

7

7

BLU

8

8

BLU

9

9

BLU

10 10

WP-027

WHI

11111

CN10

(WHI)

Varistor

CN21

(WHI)

Wireless Unit Assembly

21

CN11

(BLK)

1
1

Line
Filter

1

1

2

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

10

10

11

11

BLK

CN51

CN02

6 6

CN31

(WHI)

2 2

4 4

CN32
(WHI)

DC5V
DC12V
DC15V

Main P.C Board

MCC-5045

1 32 5

CN81
(WHI)

11

33
44
55

DC Motor

Fan Motor

WHI

1 1

11

YEL

22

YEL

3 3

33

YEL

44

YEL

5 5

55

Louver Motor

CN22

(WHI)

1
2
3
4

Color indication

YEL:YELLOW
BLK:BLACK
RED:RED
BLU:BLUE

Power Supply Circuit

WHI:WHITE
GRN&YEL:
GREEN & YELLOW

6

4

– 14 –

IIndoor Unit

FILE NO. SVM-12087

6. SPECIFICATIONS OF ELECTRICAL PARTS

No.

1

Fan motor
(for indoor)

2

Room temp. sensor (TA-sensor)

3

Heat exchanger temp. sensor (TC-sensor)

4

Heat exchange temp. sensor (TCJ-sensor)

5 Louver motor

Parts name

Type

MF-340-30-3

( — )

( — )

( — )

MSBPC20F04

Specifications

DC340V, 30W

10kΩ at 25°C

10kΩ at 25°C

10kΩ at 25°C

Output (Rated) 1W, 16 poles, DE12V

– 15 –

7. REFRIGERANT CYCLE DIAGRAM

FILE NO. SVM-12087

P

Pressure measurement
Gauge attaching port

Vacuum pump connecting port

Deoxidized copper pipe
Outer dia. : 12.7mm

Thickness : 0.8mm

INDOOR UNIT

Indoor heat

exchanger

Cross flow fan

Deoxidized copper pipe
Outer dia. : 6.35mm

Thickness : 0.8mm

Sectional shape
of heat insulator

T1 Temp. measurement

TCJ

TC

TA

difference: * m

Allowable height

Per 1 unit

Max. : * m
Min. : * m
Chargeless : * m
Charge : * m

Total

Max. : * m

Allowable pipe length

OUTDOOR UNIT *

NOTE :

* Refer to SERVICE MANUAL of connected outdoor unit.

The specification is different to each outdoor unit.

NOTE:

Gas leak check position

– 16 –

Indoor Unit

FILE NO. SVM-12087

8. CONTROL BLOCK DIAGRAM

Heat Exchanger Sensor (Tcj)

Heat Exchanger Sensor (Tc)

Room Temperature Sensor (Ta)

Infrared Rays Signal Receiver

and Indication

Initializing Circuit

Clock Frequency

Oscillator Circuit

Power Supply Circuit

Converter (D.C circuit)

Noise Filter

M.C.U.

Functions

• Cold draft preventing Function

• 3-minute Delay at Restart
for Compressor

• Fan Motor Starting Control

• Processing
(Temperature Processing)

• Timer

• Serial Signal Communication

• Clean Function

Serial Signal Transmitter/Receiver

Indoor Unit Control Unit

Louver

Motor

Louver Motor
Drive Control

Indoor Fan

Motor Control

Indoor

Fan Motor

From Outdoor Unit

220-240V ~50Hz

220V ~60Hz

REMOTE CONTROLLER

Serial Signal Communication

(Operation Command and Information)

Remote Controller

Infrared Rays, 36.7kHz

Operation (START/STOP)

Operation Mode Selection

AUTO, COOL, DRY, HEAT

Thermo. Setting

Fan Speed Selection

ON TIMER Setting

OFF TIMER Setting

Louver AUTO Swing

Louver Direction Setting

ECO

Hi-POWER

COMFORT SLEEP

QUIET

QUIET

SLEEP (1, 3, 5, 9 OFF TIMER)

– 17 –

9. OPERATION DESCRIPTION

FILE NO. SVM-12087

9-1. Outline of Air Conditioner Control

This air conditioner is a capacity-variable type air
conditioner, which uses DC motor for the indoor fan
motor and the outdoor fan motor. And the capacity­proportional control compressor which can change the
motor speed in the range from 11 to 120 rps is
mounted. The DC motor drive circuit is mounted to the
indoor unit. The compressor and the inverter to control
fan motor are mounted to the outdoor unit.

The entire air conditioner is mainly controlled by the
indoor unit controller.

The indoor unit controller drives the indoor fan motor
based upon command sent from the remote controller,
and transfers the operation command to the outdoor
unit controller.
The outdoor unit controller receives operation com­mand from the indoor unit side, and controls the
outdoor fan and the pulse motor valve. (PMV)
Besides, detecting revolution position of the compres­sor motor, the outdoor unit controller controls speed of
the compressor motor by controlling output voltage of
the inverter and switching timing of the supply power
(current transfer timing) so that motors drive according
to the operation command.
And then, the outdoor unit controller transfers reversely
the operating status information of the outdoor unit to
control the indoor unit controller.

As the compressor adopts four-pole brushless
DC motor, the frequency of the supply power
from inverter to compressor is two-times cycles
of the actual number of revolution.

1. Role of indoor unit controller

The indoor unit controller judges the operation
commands from the remote controller and assumes
the following functions.

• Judgment of suction air temperature of the indoor
heat exchanger by using the indoor temp. sensor.
(TA sensor)

• Judgment of the indoor heat exchanger tempera­ture by using heat exchanger sensor (TC sensor)
(Prevent-freezing control, etc.)

• Louver motor control

• Indoor fan motor operation control

• LED (Light Emitting Diode) display control

• Transferring of operation command signal
(Serial signal) to the outdoor unit

• Reception of information of operation status
(Serial signal including outside temp. data) to the
outdoor unit and judgment/display of error

• Air purifier operation control

2. Role of outdoor unit controller

Receiving the operation command signal
(Serial signal) from the indoor unit controller, the
outdoor unit performs its role.

• Compressor operation control

• Operation control of outdoor fan motor

• PMV control

• 4-way valve control



Operations followed to judgment



of serial signal from indoor side.



• Detection of inverter input current and current
release operation

• Over-current detection and prevention operation
to IGBT module (Compressor stop function)

• Compressor and outdoor fan stop function when
serial signal is off (when the serial signal does not
reach the board assembly of outdoor control by
trouble of the signal system)

• Transferring of operation information (Serial
signal) from outdoor unit controller to indoor unit
controller

• Detection of outdoor temperature and operation
revolution control

• Defrost control in heating operation (Temp.
measurement by outdoor heat exchanger and
control for 4-way valve and outdoor fan)

3. Contents of operation command signal
(Serial signal) from indoor unit controller to
outdoor unit controller

The following three types of signals are sent from
the indoor unit controller.

• Operation mode set on the remote controller

• Compressor revolution command signal defined

by indoor temperature and set temperature
(Correction along with variation of room tempera­ture and correction of indoor heat exchanger
temperature are added.)

• Temperature of indoor heat exchanger

• For these signals ([Operation mode] and [Com-

pressor revolution] indoor heat exchanger tem­perature), the outdoor unit controller monitors the
input current to the inverter, and performs the
followed operation within the range that current
does not exceed the allowable value.

4. Contents of operation command signal
(Serial signal) from outdoor unit controller
to indoor unit controller

The following signals are sent from the outdoor unit
controller.

• The current operation mode

• The current compressor revolution

• Outdoor temperature

• Existence of protective circuit operation

For transferring of these signals, the indoor unit
controller monitors the contents of signals, and
judges existence of trouble occurrence.

Contents of judgment are described below.

• Whether distinction of the current operation
status meets to the operation command signal

• Whether protective circuit operates
When no signal is received from the outdoor

unit controller, it is assumed as a trouble.

– 18 –

FILE NO. SVM-12087

9-2. Operation Description

9-2. 1. Basic operation ........................................................................................................... 20

1. Operation control ................................................................................................... 20

2. Cooling/Heating operation ..................................................................................... 21

3. AUTO operation...................................................................................................... 21

4. DRY operation ........................................................................................................ 21

2. Indoor fan motor control.............................................................................................. 22

3. Capacity control .......................................................................................................... 24

4. Current release control ............................................................................................... 24

5. Release protective control by temperature of indoor heat exchanger ........................ 25

6. Louver control ............................................................................................................. 26

1) Louver position....................................................................................................... 26

2) Air direction adjustment ......................................................................................... 26

3) Swing ..................................................................................................................... 26

7. Defrost control (Only in heating operation)................................................................. 27

8. ECO operation ............................................................................................................ 27

9. Temporary operation................................................................................................... 27

10. Pulse motor valve (PMV) control ................................................................................ 28

11. Self-Cleaning function ................................................................................................ 28

12. Remote Controller-A or B selection ............................................................................ 29

13. QUIET mode ............................................................................................................... 30

14. COMFORT SLEEP ..................................................................................................... 30

15. Short Timer ................................................................................................................. 30

16. One Touch Comfort ..................................................................................................... 31

17. Hi POWER Mode ........................................................................................................ 31

9-3. Auto Restart Function

9-3-1. How to Set the Auto Restart Function .................................................................... 32

9-3-2. How to Cancel the Auto Restart Function.............................................................. 33

9-3-3. Power Failure during Timer Operation.................................................................... 33

9-4. Remote Controller

9-4-1. Remote Controller and Its Functions ..................................................................... 34

9-4-2. Operation of Remote Controller .............................................................................. 34

9-4-3. Names and Functions of Indications on Remote Controller ................................ 37

– 19 –

FILE NO. SVM-12087

Item

1. Basic
operation

Operation flow and applicable data, etc.

1. Operation control

Receiving the user’s operation condition setup, the operation statuses of indoor/outdoor units are
controlled.

1) The operation conditions are selected by the remote controller as shown in the below.

2) A signal is sent by ON button of the remote controller.

3) The signal is received by a sensor of the indoor unit and processed by the indoor controllers as
shown in the below.

4) The indoor controller controls the indoor fan motor and louver motor.

5) The indoor controller sends the operation command to the outdoor controller, and sends/
receives the control status with a serial signal.

6) The outdoor controller controls the operation as shown in the left, and also controls the com­pressor, outdoor fan motor, 4-way valve and pulse motor valve.

Selection of

operation conditions

ON/OFF

Remote controller

Control contents of remote controller

• ON/OFF (Air conditioner / Air purifier)

• Operation select (COOL /HEAT / AUTO / DRY)

• Temperature setup

• Air direction

• Swing

• Air volume select
(AUTO / LOW / LOW+ / MED / MED+ / HIGH)

• ECO • COMFORT SLEEP

• ON timer setup • QUIET

• OFF timer setup • PRESET

• Hi-POWER • ONE-TOUCH

Description

Signal receiving

Indoor unit control

Operation command

Serial signal send/receive

Serial signal send/receive

Outdoor unit control

Indoor unit

Indoor unit control

• Command signal generating function of
indoor unit operation

• Calculation function (temperature calculation)

• Activation compensation function of indoor fan

• Cold draft preventive function

• Timer function

• Indoor heat exchanger release control

Outdoor unit

Outdoor unit control

• Frequency control of inverter output

• Waveform composite function

• Calculation function
(Temperature calculation)

• AD conversion function

• Quick heating function

• Delay function of compressor reactivation

• Current release function

• GTr over-current preventive function

• Defrost operation function

Inverter

• Indoor fan motor

• Louver motor

~

• Compressor

• Outdoor fan motor

• 4-way valve

• Pulse Motor valve
(PMV)

– 20 –

FILE NO. SVM-12087

Item

1. Basic
operation

Operation flow and applicable data, etc.

2. Cooling/Heating operation

The operations are performed in the following parts by controls according to cooling/heating conditions.

1) Receiving the operation ON signal of the remote controller, the cooling or heating operation signal
starts being transferred form the indoor controller to the outdoor unit.

2) At the indoor unit side, the indoor fan is operated according to the contents of “2. Indoor fan motor
control” and the louver according to the contents of “8. Louver control”, respectively.

3) The outdoor unit controls the outdoor fan motor, compressor, pulse motor valve and
4-way valve according to the operation signal sent from the indoor unit.

Operation ON

Indoor unit control

Sending of operation command signal

Outdoor unit control

3. AUTO operation

Selection of operation mode
As shown in the following figure, the operation starts by
selecting automatically the status of room temperature
(Ta) when starting AUTO operation.

*1. When reselecting the operation mode, the fan speed

is controlled by the previous operation mode.

Ta

Cooling operation

Ts + 1

Monitoring (Fan)

Ts – 1

Heating operation

Setup of remote controller

Indoor fan motor control / Louver control / Operation Hz
Control (Requierment)

Compressor revolution control / Outdoor fan motor control /
Operation Hz control (Include limit control)
4-way valve control In cooling operation: ON

Pulse Motor valve control

[ ]

In heating operation: OFF

1) Detects the room temperature (Ta) when
the operation started.

2) Selects an operation mode from Ta in
the left figure.

3) Fan operation continues until an
operation mode is selected.

4) When AUTO operation has started
within 2 hours after heating operation
stopped and if the room temperature is
20°C or more, the fan operation is
performed with ”Super Ultra LOW” mode
for 3 minutes.
Then, select an operation mode.

5) If the status of compressor-OFF
continues for 15 minutes the room
temperature after selecting an operation
mode (COOL/HEAT), reselect an
operation mode.

Description

4. DRY operation

DRY operation is performed according to the difference
between room temperature and the setup temperature
as shown below.

In DRY operation, fan speed is controlled in order to
prevent lowering of the room temperature and to avoid
air flow from blowing directly to persons.

[C]

Ta

+

1.0

+

0.5

L (W5)

(W5+W3) / 2

SL (W3)

Tsc

Fan speed

– 21 –

1) Detects the room temperature (Ta) when
the DRY operation started.

2) Starts operation under conditions in the
left figure according to the temperature
difference between the room tempera­ture and the setup temperature (Tsc).
Setup temperature (Tsc)

= Set temperature on remote controller

(Ts) + (0.0 to 1.0)

3) When the room temperature is lower
1°C or less than the setup temperature,
turn off the compressor.

FILE NO. SVM-12087

Item

2. Indoor fan
motor control

COOL ON

Fan speed setup

AUTO

Ta

[°C]

+2.5

a

+2.0

b

+1.5

c

+1.0

Operation flow and applicable data, etc.

<In cooling operation>

(This operation controls the fan speed at indoor unit side.)
The indoor fan (cross flow fan) is operated by the phase-

control induction motor. The fan rotates in 5 stages in
MANUAL mode, and in 5 stages in AUTO mode, respectively.
(Table 1)

MANUAL

Indication

L

L+

M

M+

H

(Fig. 1)

Fan speed

W6

(L + M) / 2

W9

(M + H) / 2

WC

(Fig. 2)

Air volume AUTO

M+(WB)

*3

*4

*5

*3 : Fan speed = (M + –L) x 3/4 + L

*4 : Fan speed = (M + –L) x 2/4 + L

*5 : Fan speed = (M + –L) x 1/4 + L

Description

∗∗

∗ Symbols

∗∗

UH: Ultra High
H : High
M+: Medium+
M : Medium
L+ : Low+
L: Low
L- : Low–
UL : Ultra Low
SUL : Super Ultra Low

* The fan speed broadly varies due

to position of the louver, etc.
The described value indicates one
under condition of inclining
downward blowing.

1) When setting the fan speed to L,
L+, M, M+ or H on the remote
controller, the operation is
performed with the constant
speed shown in Fig. 1.

2) When setting the fan speed to
AUTO on the remote controller,
revolution of the fan motor is
controlled to the fan speed level
shown in Fig. 2 and Table 1
according to the setup tempera­ture, room temperature, and heat
exchanger temperature.

+0.5

Ts c

d

L(W6)

e

(Table 1) Indoor fan air flow rate

Fan

speed

COOL HEAT DRY

level

WF
WE
WD
WC
WB
WA
W9
W8
W7
W6
W5
W4
W3
W2
W1

H

M+ M

ML+

L+ L– L+

L– UL L–
UL UL

SUL SUL

UH

H

M+

L

SUL

(Linear approximation
from M+ and L)

Fan speed Air flow rate

(rpm) (m

1250 1156
1250 1156
1250 1156
1230 1134
1130 1034
1070 957

1030 913

900 768
860 669
850 713
810 669
750 603
650 492
500 325
500 325

3

/h)

– 22 –