Mitsubishi PUHZ-W90VHA Service Manual

AIR TO WATER HEAT PUMP

SERVICE MANUAL

R410A

August 2007

No. OCH419

[model name]

PUHZ-W90VHA

[Service Ref.]

PUHZ-W90VHA

CONTENTS

Note:

• This manual describes only

service data of PUHZ-W90VHA.

• RoHS compliant products have

<G> mark on the spec name plate.

PUHZ-W90VHA

1. SAFETY PRECAUTION

2. SPECIFICATIONS

3. DATA

4. OUTLINES AND DIMENSIONS

5. WIRING DIAGRAM

6. WIRING SPECIFICATIONS

7. REFRIGERANT SYSTEM DIAGRAM

8. TROUBLESHOOTING

9. DISASSEMBLY PROCEDURE

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PARTS CATALOG (OCB419)

...................

2

4

5

7

8

9

10

11

38

1

SAFETY PRECAUTION

1-1. ALWAYS OBSERVE FOR SAFETY

Before obtaining access to terminal, all supply ciucuits must be disconnected.

1-2. CAUTIONS RELATED TO NEW REFRIGERANT

Cautions for units utilizing refrigerant R410A

Do not use refrigerant other than R410A.

If other refrigerant (R22 etc.) is used, chlorine in refrigerant can cause deterioration of refrigerant oil etc.

Use a vacuum pump with a reverse flow check valve.

Vacuum pump oil may flow back into refrigerant cycle and that can cause deterioration of refrigerant oil etc.

Use the following tools specifically designed for use with R410A refrigerant.

The following tools are necessary to use R410A refrigerant.

Tools for R410A
Gauge manifold
Charge hose

Gas leak detector

Torque wrench

Vacuum pump adaptor
Electronic refrigerant

charging scale

Keep tools with care.

If dirt, dust or moisture enters into refrigerant cycle, that can cause deterioration of refrigerant oil or malfunction
of compressor.

Do not use a charging cylinder.

If a charging cylinder is used, the composition of refrigerant will change and the efficiency will be lowered.

Ventilate the room if refrigerant leaks during operation. If refrigerant comes into contact with
a flame, poisonous gases will be released.

Charge refrigerant from liquid phase of gas cylinder.

If the refrigerant is charged from gas phase, composition change may occur in refrigerant and the efficiency
will be lowered.

[1] Cautions for service

(1) Perform service after recovering the refrigerant left in unit completely.
(2) Do not release refrigerant in the air.
(3) After completing service, charge the cycle with specified amount of refrigerant.

[2] Additional refrigerant charge

When charging directly from cylinder

· Check that cylinder for R410A on the market is syphon type.

· Charging should be performed with the cylinder of syphon stood vertically. (Refrigerant is charged from liquid phase.)

2

Unit

Gravimeter

[3] Service tools

Use the below service tools as exclusive tools for R410A refrigerant.

No. Specifications

 Gauge manifold ·Only for R410A

·Use the existing fitting

·Use high-tension side pressure of 5.3MPa·G or over.

 Charge hose ·Only for R410A

·Use pressure performance of 5.09MPa·G or over.

 Electronic scale

 Gas leak detector ·Use the detector for R134a, R407C or R410A.

 Adaptor for reverse flow check ·Attach on vacuum pump.

 Refrigerant charge base

 Refrigerant cylinder ·Only for R410A Top of cylinder (Pink)

Cylinder with syphon

 Refrigerant recovery equipment

specifications

. (UNF1/2)

1-3. CAUTIONS FOR REFRIGERANT PIPING WORK

Tools for R410A (The following table shows whether conventional tools can be used or not.)

Tools and materials Use R410A tools Can R22 tools be used?
Gauge manifold

Charge hose
Gas leak detector

Refrigerant recovery equipment
Refrigerant cylinder
Safety charger

Charge valve

Vacuum pump

Bender
Pipe cutter
Welder and nitrogen gas cylinder
Refrigerant charging scale

Vacuum gauge or thermis­tor vacuum gauge and
vacuum valve
Charging cylinder

: Prepare a new tool. (Use the new tool as the tool exclusive for R410A.)
: Tools for other refrigerants can be used under certain conditions.
: Tools for other refrigerants can be used.

Air purge, refrigerant charge
and operation check
Gas leak check
Refrigerant recovery
Refrigerant charge
Prevent compressor malfunction

when charging refrigerant by
spraying liquid refrigerant

Prevent gas from blowing out
when detaching charge hose

Vacuum drying and air
purge

Bend the pipes
Cut the pipes
Weld the pipes
Charge refrigerant
Check the degree of vacuum. (Vacuum

valve prevents back flow of oil and refri­gerant to thermistor vacuum gauge)
Refrigerant charge

Tool exclusive for R410A
Tool exclusive for R410A
Tool for HFC refrigerant
Tool exclusive for R410A
Tool exclusive for R410A
Tool exclusive for R410A

Tool exclusive for R410A

Tools for other refrigerants can
be used if equipped with adop­ter for reverse flow check
Tools for other refrigerants can be used
Tools for other refrigerants can be used
Tools for other refrigerants can be used
Tools for other refrigerants can be used
Tools for other refrigerants
can be used

Tool exclusive for R410A

(Usable if equipped

with adopter for rever­ se flow)

Can R407C tools be used?

(Usable if equipped

with adopter for rever­ se flow)

33

2

SPECIFICATIONS

Power supply Phase

㱢

Voltage V

Heating Capacity kW Heating(A2/W35)
(A2/W35) 2+)blub-yrD(erutarepmetriaedistuOPOC 㷄

1

230

50

7.0

3.40

2.06

noitidnocgnitarepolanimoNzHycneuqerF

etriaedistuOWktupnirewoP 㷄

1+)blub-teW(erutarepm

25.8

Heating Capacity kW Heating(A7/W35)
(A7/W35) 7+)blub-yrD(e

Cooling Capacity kW Cooling(A35/W7)
(A35/W7) EER

(COP) Outside air temperature (Dry-bulb) +35㷄

nimoN 㷄

Cooling Capacity kW Cooling(A35/W18)
(A35/W18) EER

(COP) Outside air temperature (Dry-bulb) +35㷄

animoN 㷄

9.0

3.90

2.31

25.8

7.1

2.00

3.55

20.4

7.1

3.70

1.92

20.4

rutarepmetriaedistuOPOC 㷄

6+)blub-teW(erutarepmetriaedistuOWktupnirewoP 㷄

tretaWnim/LwolfretawlanimoN 㷄

42+)blub-teW(erutarepmetriaedistuOWktupnirewoP 㷄

42+)blub-teW(erutarepmetriaedistuOWktupnirewoP 㷄

regnahcxetaehetalPtinuroodtuO

Model name ALFA LAVAL
Running current Heating

Cooling

(A7/W35) 04-03HCAA
(A35/W7) A

External finish

Start type
Protection devices

PUHZ-W90VHA

10.3

15.7

23.0

Galvanized plate

Munsell 3Y 7.8/1.1

Linear expansion valve

Hermetic twin rotary

TNB220FLHM1

1.3

Line start

HP switch

w

mm4.04:AAtnerruc.xaM

Ref.IN

(Heating)

mm2.862:BgnisacretuO

mm39:WlortnoctnaregirfeR

mm523:HrosserpmoC

mm96:DledoM

Ref.OUT
(Heating)

4WktuptuorotoM

setalp0

B

Thermistor

(TH32)

A

D

Water OUT

H

Water IN

Discharge thermo

WretaehesacknarC

Heat exchanger (Air)

(Water)

Fan Fan(drive)×No.

Fan motor output

Air flow

kW

3

m

/min

(CFM)
Defrost method
Noise level Heating dB

Cooling dB

Dimensions Width mm(in.)

Depth mm(in.)
Height mm(in.)

Refrigerant

Quantity kg(lbs)
Guaranteed operating Heating
range (Outdoor) Cooling

㷄
㷄

nim/LwolfretaW

0.67 (FV50S)

䊷

Plate fin coil

Plate heat exchanger

Propeller fan × 1

0.060
55

(1,940)

Reverse cycle

*2

49

*2

49

950 (37-3/8)

*1

330 +30

(13+1-3/16)

943 (37-1/8)

)sbl(gkthgieW

79 (174)

R410A

2.4 (5.3)

-20 䌾 +35

*4

-5

䌾 +46

10.0 䌾 25.8

65

]

60

55

*3

50

45

Maximum outlet water temptemperature [

40

-20 -15

*1 grill
*2 at distance of 1m from outdoor unit
*3 Hot gas with four-way valve
*4 With the optional air outlet guide, the operation at

-15㷄㩷outdoor temperature is possible.

-10 -5 0 5 10

Ambient t emperature []

erutarepmetretawteltuomumixaML)ledoM(liO

53+/03+)teltuo/telni(erutarepmetretaWnim/LwolfretawlanimoN 㷄

53+/03+)teltuo/telni(erutarepme

7+/21+)teltuo/telni(erutarepmetretaWnim/Lwolfretawla

81+/32+)teltuo/telni(erutarepmetretaWnim/Lwolfretawl

4

5

3

DATA

3-1. NOISE CRITERION CURVES

MICROPHONE

1.5m

1m

UNIT

GROUND

PUHZ-W90VHA

90

80

70

60

50

40

MODE

COOLING

HEATING

SPL(dB)

49
49

LINE

NC-70

NC-60

NC-50

NC-40

30

20

OCTAVE BAND SOUND PRESSURE LEVEL, dB (0 dB = 0.0002 bar)

10

APPROXIMATE
THRESHOLD OF
HEARING FOR
CONTINUOUS
NOISE

63 125 250 500 1000 2000 4000 8000

BAND CENTER FREQUENCIES, Hz

NC-30

NC-20

3-2. STANDARD OPERATION DATA

Mode Cooling (A35/W7) Heating (A7/W35)

Capacity W 7,100 9,000

Total

Input kW 3.55 2.31

Outdoor unit PUHZ-W90VHA

Phase, Hz 1, 50

Voltage V 230

Electrical circuit

Current A 15.7 10.3

Discharge pressure MPa 2.74 2.21

Suction pressure MPa 0.73 0.64

Discharge temperature

Condensing temperature

Refrigerant circuit

Suction temperature

Flow volume L/min 20.4 25.8

Water

Outlet water temperature

conditions

D.B.

Intake air temperature

Outdoor

conditions

The unit of pressure has been changed to MPa based on international SI system.
The conversion factor is : 1(MPa)=10.2(kgf/cm

W.B.

 74 65

 47









2

)

3-1

735

35 7

24 6

38

6

4

OUTLINES AND DIMENSIONS

PUHZ-W90VHA

24

39

ISO 228/1-G1 B

2-U Shaped notched holes

(Foundfation Bolt M10)

26998

417
370 19

28

53

2-12×36 oval holes

(Foundation Bolt M10)

Detail

Scale 1:3

Service panel

Left······Power supply wiring

Terminal Connections

Handle for moving

Right······Controller wiring

see Detail

119

34

40

Power supply wiring hole

(2-:27Knock Out)

682

Rear cover

Front cover

Unit : mm

Drain hole

(5-:33)

Rear Air Intake

Installation Feet

175 600 175

Side Air Intake

FOUNDATION

Please secure the unit firmly

with 4 foundation (M10) bolts.

(Bolts and washers must be

2 SERVICE SPACE 3 FOUNDATION BOLTS

Dimensions of space needed

for service access are

shown in the below diagram.

<Foundation bolt height>

purchased locally.)

Over300

500

330

30

Less than

Over

Over

500

Air Discharge

30

950

322

Handle for moving

Side Air Intake

Handle for moving

Rear Air Intake

473

943

Handle for moving

23

30 220 145 145 145

81 219

Over10

Service space

Over 10mm

Over 300mm

(4''

1 FREE SPACE (Around the unit)

The diagram below shows a

basic example.

Explantion of particular details are

given in the installation manuals etc.

Over 10mm

Over 00mm

57

Air Intake

Water OUT

Water IN

Handle for moving

77

WIRING DIAGRAM5

PUHZ-W90VHA

SYMBOL NAME SYMBOL NAME
TB1
TB2 Terminal Block<Controller>
TB3 Terminal Block<Controller>
MC
MF1
21S4
SV Solenoid Valve<Bypass Valve
63H
63HS
TH3
TH4
TH6
TH7
TH8

Terminal Block<Power Supply>

Motor for Compressor
Fan Motor

Solenoid Valve<Four-Way Valve

High Pressure Switch
High Pressure Sensor

Thermistor<Liquid>

Thermistor<Discharge>
Thermistor<Plate HEX Iiquid>
Thermistor<Ambient>
Thermistor<Heatsink>

>

>

P.B.

TABU/V/W
TABS/T
TABP1/P2
TABN1/N2

N.F.

LI,LO
NI,NO
EI,E2
52C

Power Circuit Board

Connection Terminal<U/V/W-Phase>
Connection Terminal<L/N-Phase>
Connection Terminal<DC Voltage>
Connection Terminal<DC Voltage>
Diode bridgeDS2, DS3
Power ModuleIPM

Noise Filter Circuit Board

Connection Terminal<L-Phase>

Connection Terminal<N-Phase>

Connection Terminal<Ground>
52C Relay

TH32 Thermistor<Inlet water>
LEV-A, LEV-B
DCL

Electronic Expansion Valve

Reactor

ACTM Active Filter Module

63HS

MF1

MS
3~

C. B.

1

CNS

(WHT)

TH7

TH6 TH3 TH4

TH32

t° t° t° t°

7

CNF1
(WHT)

3

2

1

CNDC

(PNK)

3

1

12

TH32

(BLK)

TRANS

t°

CNAC
(WHT)

1

3

TH7/6
(RED)

2

4

TH3

(WHT)

63H

2

TH4

(WHT)

1

3

63H

(YLW)

CN2

(WHT)

17

7

F3

F4

11121

63HS

(WHT)

21S4
(GRN)

LEV-A

34

21S4 SV

M

LEV-A
(WHT)

X52

LEV-B

M

1613

61

LEV-B

CNVMNT

(RED)

(WHT)

CN4

(WHT)

12

2

X55

SV2

1313

(BLU)

1

CNMNT

(WHT)

CN52C

(RED)

12

*1 MODEL SELECT

1=ON, 0=OFF

5

SW8

LED3

2

SYMBOL NAME

C.B.

SW1
SW2
SW6
SW8
LED3
F3, F4
X52, X55

I.F.

SW6

12345 6

Controller Circuit Board
Switch<Function Switch>
Switch<Function Switch>
Switch<Model Select>
Switch<Function Switch>
LED<Operation/Inspection Indicators>
Fuse<T6.3AL250V>
Relay
Interface Circuit Board

00101 0

*1

SW6

SW1

CNDM

CN3S
(RED)

(WHT)

CN51
(WHT)

SW2

1

3
1

3
1

5

6

3

6

5

3

I. F.

1

CNIF1

(RED)

6

1

CNIF2

(WHT)

3

1

CNIF3

(WHT)

5

1

CNIF4

(WHT)

7

3

4

7

TH8

t°

N. F.

BLU

WHT

52C

U

RED

A3 A4

NO

NI

U

BLK

BLU

CONTROLLER

BLU

TB2

1

2

E2

1

2

CN5

EI

PNK

A5

(BLK)

CN52C

(RED)

B1

3

YLW

2

2

ORN

B2 B3

BRN

TB3

LO

P. B.

TABV

WHT

V

MS
3~

BLK

CNDC

BLK

W

MC

L1

(PNK)

TABW

2

1

L2

ACTM

3

4

WHT

16

TABN1

N1
N2

BLK

P

Io

TABT

TABS

TABP1

BLU

WHT

RED

BLU

RED

N

L

POWER SUPPLY

~/N 230V 50Hz

YLW/GRN

TB1

3

1

(RED)

CNAC2

3

1

(WHT)

CNAC1

5

RED

A1

LI

WHT

A2

DS3

DS2

U

TABN2

WHT

RED

WHT

1

CNAF
(WHT)

6
1

CN2

IPM

(WHT)

7

TABP2

RED

1

CN3

(WHT)

2

2

1

CN5

(RED)

2

2

1

CN4

(WHT)

2

TABN
TABP

TABU

RED

U

DCL

RED

BLK

8

9

WIRING SPECIFICATIONS6

FIELD ELECTRICAL WIRING (power wiring specifications)

Outdoor unit power supply ~/N (single), 50Hz, 230 V

Outdoor unit Circuit Breaker capacity *1 25 A

)

2

Outdoor unit power supply, earth 3 × Min.4

Wiring

Controller-Outdoor unit *2 8 × Min.0.5 (polar)

size (mm

Wire No. ×

Outdoor unit L-N (single) AC 230 V

rating

Circuit

Controller-Outdoor unit DC 12 V

*1. A breaker with at least 3.0 mm contact separation in each pole shall be provided. Use non-fuse breaker (NF) or earth leak-

age breaker (NV).

*2. Max. 20 m

Notes: 1. Wiring size must comply with the applicable local and national codes.

2.

Power supply cables and the cables between Controller and Outdoor unit shall not be lighter than polychloro-

SUHQHVKHDWKHGÀH[LEOHFDEOHV

(Design 60245 IEC 57

3. Be sure to connect the cables between Controller and Outdoor unit directly to the units (no intermediate
connections are allowed).
Intermediate connections may result in communication errors. If water enters at the intermediate connection

SRLQWLWPD\FDXVHLQVXI¿FLHQW

insulation to ground or a poor electrical contact .
(If an intermediate connection is necessary, be sure to take measures to prevent water from entering the
cables.)

4. Install an earth longer than other cables.

)

REFRIGERANT SYSTEM DIAGRAM7

PUHZ-W90VHA

Water OUT

Plate HEX

Water IN

TH32

TH6

CHECK/V

CHECK/V

Receiver

Strainer
(#100)

LEV-B

Strainer(#100) Strainer(#100)

REV/V

S/V

Strainer
(#100)

LEV-A

P-Sensor

COMP

CHECK/V

H/P SW

TH4

TH7

TH3

Distributor

TH8 P/B

Refrigerant flow in heating

Refrigerant flow in cooling

Symbol

COMP

H/P SW

Plate HEX

REV/V

S/V

CHECK/V

P-Sensor

P/B

LEV-A

LEV-B

TH32

TH3

TH4

TH6

TH7

TH8

Receiver

Part name

Compressor

High pressure switch (63H)

Plate Heat Exchanger

Reversing (4-way) valve (21S4)

Solenoid valve

Check valve

Pressure sensor (63HS)

Power board

Linear expansion valve -A

Linear expansion valve -B

Inlet water temperature thermistor

Liquid temperature thermistor

Discharge temperature thermistor

Plate HEX liquid temperature thermistor

Ambient temperature thermistor

Heatsink temperature thermistor

Receiver

Detail

DC inverter twin rotary compressor (Mitsubishi Electric Corporation)

For protection (OFF:4.15MPa)

ACH30 - 40 Plates (Alfa Laval)

Change the refrigerant circuit (Heating / Cooling) and for Defrosting

For production test use

High pressure / Low pressure / For production test use

For calculation of the condensing temperature from high pressure

Inverter power board

Heating:Secondary LEV Cooling:Primary LEV

Heating:Primary LEV Cooling:Secondary LEV

For freeze protection and for compressor frequency control

Heating:Evaporating temperature Cooling:Sub cool liquid temperature

For LEV control and for compressor protection

Heating:Sub cool liquid temperature Cooling:Evaporating temperature

For fan control and for compressor frequency control

For power board protection

For accumulation of refrigerant

10

11

TROUBLESHOOTING8

8-1. TROUBLESHOOTING

<Error code display by self-diagnosis and actions to be taken for service (summary)>

Present and past error codes are logged and displayed on the control board of outdoor unit. Actions to be taken for service,
which depends on whether or not the trouble is reoccurring at service, are summarized in the table below. Check the contents
below before investigating details.

Unit conditions at service

The trouble is reoccurring.

The trouble is not reoccurring.

Error code

Displayed

Not displayed

Logged

Not logged

Actions to be taken for service (summary)

Judge what is wrong and take a corrective action according
to “8-3. Self-diagnosis action table”.

Conduct troubleshooting and ascertain the cause of the
trouble.

Consider the temporary defects such as the work of
protection devices in the refrigerant circuit including
compressor, poor connection of wiring, noise and etc.
Re-check the symptom, and check the installation
environment, refrigerant amount, weather when the

trouble occurred, matters related to wiring

and etc.
Reset error code logs and restart the unit after finishing
service.
There is no abnormality in electrical component,
controller board, and etc.

Re-check the abnormal symptom.
Conduct troubleshooting and ascertain the cause of the

trouble
Continue to operate unit for the time being if the cause
is not ascertained.
There is no abnormality concerning of parts such as
electrical component, controller board, and etc.

.

8-2. CHECK POINT UNDER TEST RUN

Before test run

• After installation of outdoor units, piping work and electric wiring work, re-check that there is no water leakage, loosened con-

nections and incorrect polarity.

• Measure impedance between the ground and the power supply terminal block(L, N) on the outdoor unit by 500V Megger and

check that it is 1.0M or over.

+Don’t use 500V Megger to connecting wire terminal block(A1~A5, B1~B3) . This may cause malfunction.

• Turn on power supply 12 hours before test run in order to protect compressor.

• Make sure to read operation manual before test run. (Especially items to secure safety.)

8-3. SELF-DIAGNOSIS ACTION TABLE

<Abnormalities detected when the power is turned on>

Error Code

None

Abnormal point and detection method

—

 No voltage is supplied to terminal

block(TB1) of outdoor unit.
a) Power supply breaker is

b) Contact failure or disconnec-

c) Open phase (L or N phase)

 Electric power is not supplied

to power supply terminal of
noise filter circuit board / out­door power circuit board.
a) Contact failure of power

b) Open phase on the noise

 Electric power is not supplied to

outdoor controller circuit board.
a) Connector disconnected

Case

turned off.

tion of power supply
terminal

supply terminal

filter circuit board / outdoor
power circuit board
: Disconnection of terminal
LI, NI, LO, NO
: Disconnection of terminal
TABT or TABS

(CNDC)

Judgment and action

 Check following items.

a) Power supply breaker
b) Connection of power supply terminal block.

(TB1)

c) Connection of power supply terminal block.

(TB1)

 Check following items.

a) Connection of power supply terminal block.

(TB1)
Connection of terminal (LI, NI, LO, NO) on
the noise filter circuit board

b) Connection of terminal (TABT or TABS) on

outdoor power circuit board.
Refer to 8-6.

 Check connection of the CNDC connector,

on the outdoor power circuit board.
Refer to 8-6.

F5

63H connector open

Abnormal if 63H connector circuit is open
for 3 minutes continuously from being
switched on.
63H: High-pressure switch

 Disconnection of reactor (DCL)

 Disconnection of outdoor noise

filter circuit board or parts fail­ure in outdoor noise filter circuit
board

 Defective outdoor power circuit

board

 Defective outdoor controller

circuit board

 Disconnection or contact failure

of 63H connector on outdoor
controller circuit board

 Disconnection or contact failure

of 63H

 63H is working due to defective

parts.

 Defective outdoor controller

circuit board

 Check connection of reactor. (DCL)

Check connection of “L1” and “L2” on the
active filter module.(ACTM) Refer to 8-6.

 Replace outdoor noise filter circuit board.

Refer to 8-6.

 Replace outdoor power circuit board.

 Replace outdoor controller circuit board (When

items above are checked but the units cannot
be repaired.)

 Check connection of 63H connector on

outdoor controller circuit board.
Refer to 8-6.

 Check the 63H side of connecting wire.

 Check for continuity of 63H.

Replace high pressure swich if it is defective.

 Replace outdoor controller circuit board.

12

13

<Abnormalities detected while unit is operating>

Error Code

U1

Abnormal point and detection method

High pressure (High-pressure switch
63H activated)

Abnormal if high-pressure switch 63H is
activated ( + ) during compressor opera­tion.
+ 4.15 MPa

63H: High-pressure switch

Case

 Decreased water flow
 Clogged filter of water pipe
 Dirt of plate heat exchanger
 Locked water pump
 Malfunction of water pump
 Clogged or broken pipe
 Locked outdoor fan motor
 Malfunction of outdoor fan

motor

 Short cycle of outdoor unit

 Dirt of outdoor heat exchanger
 Decreased airflow caused by

defective inspection of outside
temperature thermistor
(It detects lower temperature
than actual temperature.)

 Disconnection or contact failure

of connector (63H) on outdoor
controller board

 Disconnection or contact failure

of 63H connection

 Defective outdoor controller

board

 Defective operation of linear

expansion valve

 Malfunction of fan driving

circuit

Judgment and action

~Check water circuit and repair the defect.

 Check piping and repair the defect.
~ Check outdoor unit and repair the defect.

 Check the detected temperature of outside

temperature thermistor on LED display.
(SW2: Refer to 8-7.)

~Turn the power off and check F5 is

displayed when the power is turned on again
When F5 is displayed, refer to “Judgment
and action” for F5.

 Check linear expansion valve.

Refer to 8-5.

 Replace outdoor controller board.

.

U2

U3

High discharging temperature

(1) Abnormal if discharge temperature
thermistor (TH4) detects 125 or
110 continuously for 5 minutes.
Abnormal if during defrosting and dis­ charge temperature thermistor (TH4)
detects 110 continuously for 30
minutes.

Open/short circuit of discharge
temperature thermistor (TH4)

Abnormal if open (3 or less) or short
(217 or more) is detected during
compressor operation.
(Detection is inoperative for 10 seconds to
10 minutes of compressor starting process
and for 10 minutes after or during defrost­ing.)

 Overheated compressor

operation caused by insufficient
refrigerant

 Defective thermistor
 Defective outdoor controller

board

 Defective operation of linear

expansion valve

 Disconnection or contact

failure of connector (TH4) on
the outdoor controller circuit
board.

 Defective thermistor
 Defective outdoor controller

circuit board

 Check intake super heat.

Check leakage of refrigerant.
Charge additional refrigerant.

Turn the power off and check if U3 is dis-

played when the power is turned ON again.

When U3 is displayed, refer to “Judgement

and action” for U3.

 Check linear expansion valve.

Refer to 8-5.

 Check connection of connector (TH4) on the

outdoor controller circuit board.
Check the lead wire for thermistor (TH4).
Refer to 8-6.



Check resistance value of thermistor (TH4) or
temperature on LED display.
(Thermistor/TH4: Refer to 8-5.)
(SW2 : Refer to 8-7.)

 Replace outdoor controller board.

Error Code

U4

Abnormal point and detection method

Open/short of outdoor unit thermistors
(TH3, TH32, TH6, TH7, and TH8)

Abnormal if open or short is detected
during compressor operation.
Open detection of thermistors TH3, TH32
and TH6 is not detected for 10 seconds to
10 minutes after compressor starting and
10 minutes after and during defrosting.
+Check which unit has abnormality in its
thermistor by switching the mode of
SW2.
(Refer to 8-7.)

Case

 Disconnection or contact failure

of connectors
Outdoor controller circuit
board: TH3,TH32,TH6/TH7
Outdoor power circuit board:

(

CN3

 Defective thermistor
 Defective outdoor controller

circuit board

)

Judgment and action

 Check connection of connector (TH3,TH32,

TH6/TH7) on the outdoor controller circuit board.
Check connection of connector (CN3) on the
outdoor power circuit board.
Check the lead wire for thermistor
(TH3,TH32,TH6,TH7,TH8). Refer to 8-6.

 Check resistance value of thermistor

(TH3,TH32,TH6,TH7,TH8) or check tempera­ture on LED display.
(Thermistor/TH3,TH32,TH6,TH7,TH8: Refer
to 8-5.)
(SW2 : Refer to 8-7)

 Replace outdoor controller circuit board.

U5

Thermistors

Symbol

Thermistor <Liquid temperature>

TH3

Thermistor <Inlet water temperature>

TH32

Thermistor <Plate HEX liquid temperature>

TH6

Thermistor <Ambient temperature>

TH7

Thermistor <Heatsink temperature>

TH8

Temperature of heatsink

Abnormal if heatsink thermistor(TH8)
detects temperature indicated 77.

Name

 The outdoor fan motor is

locked.

 Failure of outdoor fan motor
 Air flow path is clogged.
 Ambient temperature is high.
 Defective thermistor
 Defective input circuit of

outdoor power circuit board

 Failure of outdoor fan drive

circuit

Open detection Short detection

– 40 or below
– 40 or below
– 40 or below
– 40 or below
– 35 or below

 Check outdoor fan.

 Check air flow path for cooling.
 Check if there is something which causes

temperature rise around outdoor unit.

(Upper limit of ambient temperature is 46.)
Turn off power, and on again to check if U5
is displayed within 30 minutes.
If U4 is displayed instead of U5, refer to
error code U4.
 Check resistance value of thermistor (TH8)

or temperature by microcomputer.
(Thermistor/TH8: Refer to 8-5.)
(SW2 : Refer to 8-6)

 Replace outdoor power circuit board.
 Replace outdoor controller circuit board.

90 or above

102 or above

90 or above
90 or above

102 or above

U6

Power module

Check abnormality by driving power module
in case overcurrent is detected.
(UF or UP error condition)

 Defective outdoor power circuit

board

 Decrease of power supply voltage
 Loosen, disconnected or

reverse of compressor wiring
connection

 Defective compressor

14

 Replace outdoor power circuit board.
 Check facility of power supply.
 Correct the wiring (U

compressor. Refer to 8-6 (Outdoor power
circuit board).

 Check compressor referring to 8-4.

•V•

W phase) to

15

Error Code

U7

Abnormal point and detection method

Too low superheat due to low discharge
temperature

Abnormal if discharge superheat is
continuously detected -15 or less for
3 minutes even though linear expansion
valve has minimum open pulse after com­pressor starts operating for 10 minutes.

Case

 Disconnection or loose

connection of discharge
temperature thermistor (TH4)

 Defective holder of discharge

temperature thermistor

 Disconnection or loose connection

of linear expansion valve’s coil

 Disconnection or loose

connection of linear expansion
valve’s connector

 Defective linear expansion valve

Judgment and action

 Check the installation conditions of

discharge temperature thermistor (TH4).

 Check the coil of linear expansion valve.

Refer to 8-5.

 Check the connection or contact of LEV-A and

LEV-B on outdoor controller circuit board.

 Check linear expansion valve.

Refer to 8-4.

U8

U9

Outdoor fan motor

The outdoor fan motor is considered to be
abnormal if the rotational frequency of fan
motor is abnormal when detected during
operation.
Fan motor rotational frequency is abnor­ mal if;

• 100 rpm or below detected continuously
for 15 seconds at 20 or more outside
air temperature

• 50 rpm or below or 1500 rpm or more
detected continuously for 1 minute.

Overvoltage or voltage shortage
Synchronous signal to main circuit

Abnormal if any of followings are detected
during compressor operation;

• Decrease of DC bus voltage to 310V

• Instantaneous decrease of DC bus voltage

to 200V

• Increase of DC bus voltage to 400V

• Decrease of input current of outdoor unit
to 0.1A only if operation frequency is more
than or equal to 40Hz or compressor

current is more than or equal to 6A.

+ Check U9 error detail (SW2 all ON)

Refer to 8-7.

 Failure in the operation of

the DC fan motor

 Failure in the outdoor circuit

controller board

 Decrease of power supply voltage
 Disconnection of compressor

wiring

 Disconnection or loose connec-

tion of CN52C

 Defective ACT module
 Defective ACT module drive

circuit of outdoor power circuit
board

 Disconnection or loose connec-

tion of CNAF

 Defective 52C drive circuit of

outdoor controller circuit board

 Disconnection or loose

connection of CN5 on the
outdoor power circuit board

 Defective input current circuit

of outdoor power circuit board/
noise filter circuit board

 Check or replace the DC fan motor.

 Check the voltage of the outdoor circuit

controller board during operation.

 Replace the outdoor circuit controller

board. (when the failure is still indicated
even after performing the remedy



above.)

 Check the facility of power supply.
 Correct the wiring (U

•V•

W phase) to compressor.

Refer to 8-6 (Outdoor power circuit board).

 Check CN52C wiring.

 Replace ACT module.
 Replace outdoor power circuit board.

 Check CNAF wiring.

 Replace outdoor controller circuit board.

 Check CN5 wiring on the outdoor power

circuit board.
Refer to 8-6.

 Replace outdoor power circuit board/ noise

filter circuit board.

Ud

UF

Overheat protection

Abnormal if outdoor pipe thermistor (TH3)
detects 70or more or condensing
temperature of pressure sensor (63HS)
detects 70 or more during compressor
operation.

Compressor overcurrent interruption
(When compressor locked)

Abnormal if overcurrent of DC bus or
compressor is detected within 30 seconds
after compressor starts operating.

 Defective outdoor fan (fan

motor) or short cycle of out­door unit during cooling opera­tion

 Defective outdoor pipe
thermistor (TH3)
 Defective outdoor controller

board

 Defective pressure sensor

Decrease of power supply voltage


 Looseness, disconnection or

converse of compressor wiring
connection

 Defective compressor
 Defective outdoor power board
 Decreased water flow
 Clogged filter of water pipe
 Clogged plate heat exchanger
 Locked water pump
 Malfunction of water pump

 Check outdoor unit air passage.

 Turn the power off and on again to check

the error code. If U4 is displayed, follow the
U4 processing direction.

 Check pressure by microcomputer.

(Pressure sensor/ 63HS)
(SW2: Refer to 8-7.)

 Check facility of power supply.

 Correct the wiring (U

compressor.

•V•

W phase) to

Refer to 8-6 (Outdoor power circuit board).

 Check compressor. Refer to 8-4.
 Replace outdoor power circuit board.


~

Check water circuit and repair the defect.

Error Code

UH

Abnormal point and detection method

Current sensor error or input current error

·Abnormal if current sensor detects –1.0A
to 1.0A during compressor operation.
(This error is ignored during test run.)

·Abnormal if input current is detected 32A

or input current is detected 28A or more
for 10 seconds continuously.

Case

 Disconnection of compresso

wiring

 Defective circuit of current

sensor on outdoor power
circuit board

 Decrease of power supply volt-

age

Judgment and action

 Correct the wiring (U

pressor. Refer to 8-6 (Outdoor power circuit
board).

 Replace outdoor power circuit board.
 Check the facility of power supply.

•V•

W phase) to com-

UP

Ed

Compressor overcurrent interruption

Abnormal if overcurrent DC bus or com­pressor is detected after compressor starts
operating for 30 seconds.

Serial communication error

Abnormal if serial communication
between outdoor controller circuit
board and outdoor power circuit board
is defective.

Decrease of power supply voltage


 Looseness, disconnection or

converse of compressor wiring
connection

 Defective fan of outdoor units
 Short cycle of indoor/outdoor

units

 Defective input circuit of out-

door controller board

 Defective compressor
 Decreased water flow
 Clogged filter of water pipe
 Clogged plate heat exchanger

 Locked water pump
 Malfunction of water pump

 Wire disconnection or contact

failure of connector CN2
between the outdoor controller
circuit board and the outdoor
power circuit board

 Wire disconnection or contact

failure of connector CN4
between the outdoor controller
circuit board and the outdoor
power circuit board

 Defective communication circuit

of outdoor power circuit board

 Defective communication circuit

of outdoor controller circuit board
for outdoor power circuit board

 Check facility of power supply.
 Correct the wiring (U

pressor. Refer to 8-6 (Outdoor power circuit
board).

 Check outdoor fan.
 Solve short cycle.

 Replace outdoor controller circuit board.

 Check compressor.

Refer to 8-4.
+ Before the replacement of the outdoor
controller circuit board, disconnect the wiring
to compressor from the outdoor power circuit
board and check the output voltage among
phases, U, V, W, during test run. No defect
on board if voltage among phases (U-V, V-W
and W-U) is same. Make sure to perform the
voltage check with same performing frequency.



~ Check water circuit and repair the defect.

 Check connection of each connector CN2

and CN4 between the outdoor controller
circuit board and the outdoor power circuit
board.

 Replace outdoor power circuit board.

 Replace outdoor controller circuit board.

•V•

W phase) to com-

16

17

Error Code

P6

Abnormal point and detection method

Freezing/overheating protection is working

(1)Freezing protection <Cooling mode>

Abnormal if plate heat exchanger pipe
temperature(TH6) stays at -5

or lower

for 10 seconds or abnormal if plate heat
exchanger pipe thermistor (TH6) stays at

or lower and compressor operation

-2
frequency is minimum for 5 minutes
after compressor starts operating for 6
minutes.

(2)Overheating protection <Heating mode>

Abnormal if condensing temperature of
pressure sensor(63HS) detects
Tcond.  or more and compressor oper­ation frequency is less than or equal to
30 Hz. Detection is inoperative during
defrosting.

Case

<Cooling mode>
 Reduced water flow

· Clogged filter

· Leakage of water
 Low temperature

· Low-load

· Inlet water is too cold.

 Defective water pump

Defective outdoor fan control
Overcharge of refrigerant
Defective refrigerant circuit

(clogs)

Malfunction of linear expansion

valve

<Heating mode>
 Reduced water flow

· Clogged filter

· Leakage of water
 High temperature

· Over-load

· Inlet water is too warm.
 Defective water pump

Judgment and action

<Cooling mode>

Check water piping.

 Check water pump.

 Check outdoor fan motor.
~ Check operating condition of refrigerant

circuit.

 Check linear expansion valve.

<Heating mode>

Check water piping.

 Check water pump.

P8

UE

 Overcharge of refrigerant
 Defective refrigerant circuit

 Malfunction of linear expansion

Tcond

stage-e

stage-a stage-b stage-c stage-d stage-e stage-f stage-g

Tcond 63 61 59 57 54 51 48

 Leakage or shortage of

stage-g

Pipe temperature

stage-f

-19

-18 -16 -15 -13 -12 -11 -10 -8 -7 -3 -2

Abnormal if the following conditions are
detected for continuously 3 minutes after
compressor starts operating for 10 minutes.

 Malfunction of linear

1.Cooling mode

63HS-TH72 and

T
TH3-TH74 or T

63HS-TH3< 0and

 Refrigerant circuit is clogged

TH32-TH60 and

Compressor operation frequency is 61Hz or more.

+Clogging occurs in the parts

2.Heating mode

63HS-TH322and

T
TH6-TH321and
TH7-TH31 and

Compressor operation frequency is 61Hz or more.

 Disconnection holder of

T63HS:Condensing temperature of pressure
sensor(63HS)
Thermistor
TH3:Liquid temperature
TH32:Inlet water temperature
TH6:Plate HEX Liquid temperature
TH7:Ambient temperature

Abnormal pressure of pressure sensor

 Disconnection or contact

(63HS)

Abnormal if pressure sensor(63HS) detects

0.1MPa or less.
Detection is inoperative for 3 minutes after
compressor starting and 3minutes after

 Defective pressure sensor
 Defective outdoor controller

and during defrosting.

(clogs)

valve

stage-c

stage-d

Ambient temperat ure (TH7)

refrigerant

expansion valve

with foreign objects.

which become below freezing
point when water enters in
refrigerant circuit.

thermistor

failure of connector (63HS)
on the outdoor controller
circuit board

circuit board

 Check operating condition of refrigerant

circuit.

 Check linear expansion valve.

stage-a

stage-b

[ ]

 Check intake superheat.

Check leakage of refrigerant.

 Check linear expansion valve.

 After recovering refrigerant, remove water

from entire refrigerant circuit under vacuum
more than 1 hour.

 Check temperature display on outdoor

controller circuit board.
Temperature display is indicated by setting
SW2 of outdoor controller circuit board.
Check the holder of thermistor.

 Check connection of connector (63HS) on

the outdoor controller circuit board.
Check breaking of the lead wire for thermistor
(63HS).

 Check pressure by microcomputer.

(Pressure sensor/ 63HS)
(SW2: Refer to 8-7.)

 Replace outdoor controller board.

Error Code

PE

Abnormal point and detection method

Inlet water temperature

Abnormal if the following conditions are
detected for continuously 10 seconds.

1.Cooling mode

During compressor operation
TH32 < 3

2.Heating mode (exclude defrosting)

During compressor operation
TH32 < -10

3.Defrosting mode

During compressor operation
TH32 < 0

Thermistor
TH32 : Inlet water temperature

Case

 Reduced water flow

· Clogged filter

· Leak of water
 Low temperature

· Low-load

· Low temperature inlet water

 Defective water pump

 Leakage or shortage of

refrigerant

Judgment and action

 Check water piping.

 Check water pump.

 Check intake superheat.

Check leakage of refrigerant.

18

19

8-4. HOW TO CHECK THE PARTS

1
2
3

4
5
6

M

Parts name

Check points

Disconnect the connector then measure the resistance using a tester.
(At the ambient temperature of 10~30)

Disconnect the connector then measure the resistance using a tester.
(Winding temperature 20)

TH3:Liquid pipe
temperature
TH4:Discharge
temperature
TH6:Plate Hex liquid

pipe temperature
TH7:Ambient
temperature
TH8:Heatsink
temperature
TH32:Inlet water
temperature

Normal

160k~410k

4.3k~9.6k

4.4k~9.8k
39k~105k

TH4

TH3

TH6

TH7

TH32

TH8

Abnormal

Open or short

Normal

Red - White Red - Orange

Brown - Yellow

Brown - Blue

Abnormal

46±4

Measure the resistance between the terminals using a tester.
(At the ambient temperature of 20



)

Solenoid valve coil
<Four-way valve>
(21S4)

Compressor
(MC)

Linear expansion valve
(LEV-A/ LEV-B)

Normal

Abnormal

Open or short

Open or short

Measure the resistance between the terminals using a tester.
(At the ambient temperature of 20)

Normal

1450±150

Abnormal

Open or short

Solenoid valve coil
<Bypass valve>
(SV)

Refer to the next page.Fan motor(MF1)

2350±170

0.865~0.895

Measure the resistance between the terminals using a tester.
(Winding temperature 20



)

Normal Abnormal

Open or short

W

V

U

Red

Brown

Blue
Orange

Yellow

White

PUHZ-W90VHA

Check method of DC fan motor (fan motor / outdoor controller circuit board)

Notes



· High voltage is applied to the connector (CNF1) for the fan motor. Give attention to the service.

· Do not pull out the connector (CNF1) of the motor with the power supply on.
(It may damage of the outdoor controller circuit
Self check



Symptom : The outdoor fan does not run.

Check fuse (F5) on outdoor control
circuit board.

board and fan motor.)

Is the fuse normal?

Yes

Wiring contact check

Contact of fan motor connector (CNF1)

Is there no contact failure?

Yes

Power supply check

Measure the voltage on the outdoor controller circuit. (The connector CNF1 is removed.)

No

No

Replace fan motor.
Replace

outdoor controller circuit board.

Wiring recovery

TEST POINT VDC DC280-330V (between 1 (+) and 4 (-) of CNF1)



Is the voltage normal?

 VDC DC15V (between 5 (+) and 4 (-) of CNF1)

Yes

Replace fan motor.

No

Replace outdoor control circuit board.

Check fan motor rotation.

NG

OK

Replace fan motor.

END

Check fan motor rotation.

NG

OK

Replace outdoor control circuit board.

20

END

21

8-5. HOW TO CHECK THE COMPONENTS

500

400

300

200

100

0

25

50 75 100 120

Temperature ()

Resistance (k)

<Thermistor feature chart>

Low temperature thermistors

• Thermistor <Liquid pipe> (TH3)

• Thermistor <Plate Hex liquid pipe> (TH6)

• Thermistor <Ambient> (TH7)

50

40

Thermistor R0 = 15k ± 3%
B constant = 3480 ± 2%

1

t =15exp{3480(

R

0 15k
10 9.6k

1

273+t–273

30

 4.3k

40 3.0k

)}

20 6.3k
25 5.2k

Medium temperature thermistor

• Thermistor <Heatsink> (TH8)

Thermistor R50 = 17k ± 2%
B constant = 4150 ± 3%

1

R

t =17exp{4150(

273+t–323

1

)}

0 180k
25 50k
50 17k
70 8k
90 4k

Resistance (k)

30

20

Resistance (k)

10

0

-20 -10 0 10 20 30 40 50

Temperature ()

200

150

100

50

0

25 50 75 100 125

Temperature ()

High temperature thermistor

• Thermistor <Discharge pipe> (TH4)

Thermistor R120 = 7.465k ± 2%
B constant = 4057 ± 2%

1

R

t =7.465exp{4057(

20 250k
30 160k
40 104k
50 70k
60 48k

1

273+t–393

)}

70 34k
80 24k
90 17.5k
100 13.0k
110  9.8k

Low temperature thermistor

0

10

20

30

40

50

-20 -10 0 10 20 30 40 50

Temperature()

Resistance (k)

• Thermistor <Inlet water> (TH32)

Thermistor R0 = 15k ± 2.5%

B constant = 3450 ± 2%

1

R

t =15exp{3450(

0 15k

10 9.6k

1

273+t–273

30 4.2k
40 2.9k

)}

20 6.3k

25 5.1k

22

23

Linear expansion valve

(1) Operation summary of the linear expansion valve

• Linear expansion valve open/close through stepping motor after receiving the pulse signal from the outdoor controller board.

• Valve position can be changed in proportion to the number of pulse signal.
<Connection between the indoor controller board and the linear expansion valve>

Outdoor controller board

DC12V

1

:4

:3

:2

:1

Red

Brown

Blue

Orange

Yellow

White

2

3

4

5

6

Drive circuit

:4

:3

:2

:1

LEV

3

2

M

5

1

6

4

<Output pulse signal and the valve operation>

OFF

ON

OFF

OFF

Output

5678

OFF

OFF

ON

OFF

OFF

OFF

ON

ON

OFF

ON

ON

OFF

OFF

OFF

OFF

ON

ON

OFF

OFF

ON



Output

(Phase)

:1

:2

:3

:4

234

1

ON

ON

OFF

ON

OFF

OFF

OFF

OFF

(2) Linear expansion valve operation

Connector LEV-A

LEV-B

2SHQLQJDYDOYHĺĺĺĺĺĺĺĺ
&ORVLQJDYDOYHĺĺĺĺĺĺĺĺ

The output pulse shifts in above order.

•When linear expansion valve operation stops, all output phase
become OFF.

•When the switch is turned on, 700 pulse closing valve signal will
be sent till it goes to  point in order to define the valve position.
(The pulse signal is being sent for about 20 seconds.)

When the valve moves smoothly, there is no sound or vibration
occurring from the linear expansion valve.
When the pulse number moves from  to  or when the valve is
locked, sound can be heard.
No sound is heard when the pulse number moves from  to  in
case coil is burnt out or motor is locked by open-phase.

Valve position (capacity)

Close





Extra tightning (about 32 pulse)

Open

Pulse number

•Noise can be detected by placing the ear against the screw driver
handle while putting the screw driver to the linear expansion valve.

500 pulse
Opening a valve
all the way

y

(3) How to attach and detach the coil of linear expansion valve

A

Be sure to attach the
stopper to pipe B.

B

A

<Composition>
Linear expansion valve is separable into the main body and the coil as shown in the diagram below.

Coil

Lead wire

<How to detach the coil>

Hold the lower part of the main body (shown as A) firmly so that
the main body does not move and detach the coil by pulling it
upward.
Be sure to detach the coil holding main body firmly. Otherwise,
pipes can bend due to pressure.

Stopper

Main bod

<How to attach the coil>

Hold the lower part of the main body (shown as A) firmly so that
the main body does not move and attach the coil by inserting it
downward into the main body. Then securely attach the coil stop­per to pipe B. (At this time, be careful that stress is not added
to lead wire and main body is not wounded by lead wire.) If the
stopper is not firmly attached to pipe B, coil may be detached
from the main body and that can cause defective operation of lin­ear expansion valve.
To prevent piping stress, be sure to attach the coil holding the
main body of linear expansion valve firmly. Otherwise pipe may
break.

24

25

8-6. TEST POINT DIAGRAM
Outdoor controller circuit board

&$87,21!7(6732,17LVKLJKYROWDJH

CNAC



to : Power supply
for outdoor controller
circuit board
(220V-240V AC)
 to : Not used

CN2

Connect to the out­door power circuit
board (CN2).
-:
Power circuit board

ĺ7UDQVPLWWLQJVLJQDO

to the controller circuit
board
(0-5V DC)

=HURFURVVVLJQDO

-:
(0-5V DC)

-: 18V DC
-: 16V DC
-: 16V DC

–

[

:

,,,: +

]

21S4

Four-way
valve

CNS

Not used

VCC 7(6732,17)

YROWDJHEHWZHHQSLQVRI&%'&9

63H

+LJKSUHVVXUHVZLWFK

VDC 7(6732,17)

YROWDJHEHWZHHQSLQVRI&(

: DC280V-380V

CNDC

+

DC280V-380V

&RQQHFWIURP

}

–

outdoor power
circuit board.

VSP(

7(6732,17

YROWDJHEHWZHHQSLQV

of C5B): DC 0V (when
stopped), DC 1– 6.5V
(when operated)

VFG(

7(6732,17

YROWDJHEHWZHHQULJKW

pins of PC5D, pin 3
and pin 4)

7+

7KHUPLVWRU
,QOHWZDWHUWHPSHUDWXUH!

7+

7KHUPLVWRU

<Plate Hex liquid

WHPSHUDWXUH!

7+

$PELHQWWHPSHUDWXUH!

7+

7KHUPLVWRU
/LTXLGWHPSHUDWXUH!

7+

7KHUPLVWRU
'LVFKDUJH!

)

)

SV2

Bypass valve

CN4

7UDQVPLVVLRQ

to outdoor
power circuit
board (CN4)

CN52C

Connect to the outdoor noise
filter circuit board. (CN52C)

CN51

Connect to interface
circuit board.(CN2F2)

CNDM / CN3S

Connect to interface
circuit board.(CNIF1)

/(9$%

Linear expansion valve

SW8

Function switch

SW6

Model select

SW1

Forced defrost,
detect history
record reset

SW2

2SHUDWLRQPRQLWRUIXQFWLRQ

Outdoor noise filter circuit board

LO, NO
Voltage of 220-240V AC is output.
Connect to the outdoor power
circuit board (TABS, TABT).

CNAC1, CNAC2
220-240V AC
Connect to the out­door controller cir­cuit board (CNAC).

EI
Connect to
the earth.

E2
Connect to the
earth.

CN5
Input current
Connect to the
outdoor power
circuit board
(CN5).

LI, NI
Voltage of 220-240V AC is input.
Connect to the terminal block(TB1).

26

27

Outdoor power circuit board

Brief Check of POWER MODULE
+ Usually, they are in a state of being short-circuited if they are broken.
Measure the resistance in the following points (connectors, etc.).
If they are short-circuited, it means that they are broken.

1. Check of diode bridge
TABP1-TABS, TABN1-TABS, TABP1-TABT,TABN1-TABT

2. Check of DIP-IPM

P-U, P-V, P-W, N-U, N-V, N-W

CN2
Connect to the outdoor controller circuit board
(CN2)
1-5:Transmitting signal to the outdoor

controller circuit board (0~5V DC)
2-5:Zero cross signal (0~5V DC)
3,4:18V DC
6-5:16V DC
7-5:16V DC

CN3
Thermistor (TH8)
<Heatsink>

CN5
Detection of input
current
Connect to the
outdoor noise filter
circuit board (CN5)

CN4
Connect to the
outdoor controller
circuit board (CN4)

CNAF
Connect to ACTM

DIP-IPM

CNDC
280-380V DC (+, –)
Connect to the outdoor
controller circuit board

TABS/TABT
Connect to the
outdoor noise
filter circuit
board
Voltage among
phases:220­240V AC

TABP1
Connect to

ACTM

+

TABN1
Connect to

—

ACTM

TABP2
Connect to the
ACTM

TABU/V/W
Connect to the compressor (MC)
Voltage among phases:10V~180V AC

TABN2
Connect to ACTM

Interface circuit board

CNIF1
Connect to the outdoor
controller circuit board

CNIF2
Connect to the outdoor
controller circuit board

CNIF3
Input signal
Connect to the
terminal block
(TB2, TB3)

CNIF4
Output signal
Connect to the terminal block
(TB3)

28

29

Active filter module(ACTM)

L1, L2
Connect to the
DCL (Reactor)

P
Connect to the
outdoor power
circuit board
(TABP2)

N1
Non-connect

+

Connect to the outdoor
power circuit board
(TABP1)

—

Connect to the
outdoor power
circuit board
(TABN1)

N2
Non-connect

I0
Connect to the
outdoor power
circuit board
(TABN2)

8-7. OUTDOOR UNIT OPERATION MONITOR FUNCTION

1ON23456

1 second

interval

Display

Contents to be inspected (During operation)
U1
U2
U3
U4
U5
U6
U7
U8
U9
Ud
UF

UH
UP

P6
P8

UE

PE
Ed

Abnormal high pressure (63H worked)
Abnormal high discharging temperature, shortage of refrigerant
Open/short circuit of discharging thermistor(TH4)
Open/short of outdoor unit thermistors(TH3, TH32, TH6, TH7 and TH8)
Abnormal temperature of heatsink
Abnormality of power module
Abnormality of superheat due to low discharge temperature
Abnormality in outdoor fan motor
Voltage fault, Input current sensor error
Overheat protection
Compressor overcurrent interruption (When Comp. locked)
Current sensor error, Input overcurrent interruption
Compressor overcurrent interruption
Freezing/overheating protection is working.
Abnormality of pipe temperature
Abnormal pressure of pressure sensor
Abnormality of entering water temperature
Serial communication error

Operation indicator SW2 : Indicator change of self diagnosis

SW2 setting

1ON23456

Display detail

<Digital indicator LED3 working details>

(Be sure that the 1 to 6 in the SW2 are set to OFF.)

(1) Display when the power supply is ON.
When the power supply is ON, blinking displays by turns.
Wait for 10 seconds at the longest.
(2) When the display lights (Normal operation)
Operation mode display

Explanation for display Unit

(Lighting)

SW2

LED3

The tens digit : Operation mode

Display Operation Model

O
C
H

d

OFF

COOLING

HEATING

DEFROSTING

Display during error postponement
Postponement code is displayed when
compressor stops due to the work of
protection device.
Postponement code is displayed while
error is being postponed.

(3) When the display blinks
Inspection code is displayed when compressor stops due to the work of protection devices.

The ones digit : Relay output

Display

0
1
2
3
4
5
6
7
8
A

Warming-up

Compressor

—
—
—
—
—
—
—

—
ON
ON

Compressor

—
—
—

—
ON
ON
ON
ON

—

—

4-way valve

ON
ON

ON
ON

ON

(Initial setting)

—
—

—
—

—

Solenoid valve

—

ON

—

ON

—

ON

—

ON

—
—

Display

Inspection unit

0 Outdoor unit

Display

Contents to be inspected (When power is turned on)
63H connector(yellow) is open.

F5

30

31

SW2 setting

1ON23456

1ON23456

10

1

05

1

05

1ON23456

Display detail

Pipe temperature / Liquid(TH3)
– 40~90

Explanation for display Unit

– 40~90
(When the coil thermistor detects 0 or below, “–”
and temperature are displayed by turns.)
(Example) When -10;

0.5 secs. 0.5secs. 2 secs.



1ON23456

1ON23456

1ON23456

1ON23456

Discharge temperature (TH4)
3~217

Fan steps
0~10

Compressor ON/OFF
0~9999

Compressor accumulated operation
hours
0~9999

3~217
(When the discharge thermistor detects 100 or
more, hundreds digit, tens digit and ones digit are
displayed by turns.)
(Example) When 105;

0.5 secs. 0.5secs. 2 secs.

0~10

0~9999
(When the number of times is 100 or more,
hundreds digit, tens digit and ones digit are
displayed by turns.)
(Example) When 42500 times (425 100 times);

0.5 secs. 0.5secs. 2 secs.

4

25

0~9999
(When it is 100 hours or more, hundreds digit, tens
digit and ones digit are displayed by turns.)
(Example) When 2450 hours (245 10 hours);

0.5 secs. 0.5secs. 2 secs.

2

45



Step

100 times

10 hours

1ON23456

1ON23456

1ON23456

1ON23456

Compressor running current
0~50

Compressor running frequency
0~225

0~50
+to round off at decimal point

0~255
(When it is 100Hz or more, hundreds digit, tens
digit and ones digit are displayed by turns.
(Example) When 105Hz;

0.5 secs. 0.5secs. 2 secs.

LEV-A opening pulse
0~500

0~500
(When it is 100 pulse or more, hundreds digit, tens
digit and ones digit are displayed by turns.
(Example) When 150 pulse;

0.5 secs. 0.5secs. 2 secs.

1

50

Deferred error history (1)

Deferred error
Blinking: being deferred
Lighting: deferment cancelled
“00” is displayed in case of no deferment

Operation mode when the error occured. Operation mode when the unit is stopped due to

error. The code when the SW2 is set like below.

(SW2)

A

Hz

Pulse

Code

display

Code

display

SW2 setting

Model

PUHZ-W90VHA

Code

14

1ON23456

Display detail

Pipe temperature / Liquid(TH3) when
error occured.
– 40~90

Explanation for display Unit

– 40~90
(When the coil thermistor detects 0 or below, “–”
and temperature are displayed by turns.)
(Example) When –15;

0.5 secs. 0.5secs. 2 secs.

15



1ON23456

1ON23456

1ON23456

1ON23456

Discharge temperature (TH4) when
error occured.
3~217

Compressor current when error occred.
0~50

Error code history (1) (latest)
Alternate display of faulty unit
number and error code

Error code history (2)
Alternate display of faulty unit
number and error code

3~217
(When the temperature is 100 or more, the
hundreds digit, tens digit and ones digit are
displayed by turns.)
(Example) When 130;

0.5 secs. 0.5secs. 2 secs.

1

30

0~50

When no error history,
“ 0 ” and “– –” are displayed by turns.

When no error history,
“ 0 ” and “– –” are displayed by turns.



A

Code

display

Code

display

1ON23456

1ON23456

1ON23456

Compressor operation duration
0~999

LEV-B opening when error occured.

Capacity settings

0~999
(When it is 100 minutes or more, the hundreds digit,
tens digit and ones digit are displayed by turns.)
(Example) When 245 minutes;

0.5 secs. 0.5secs. 2 secs.

2

45

0~500
(When it is 100 pulse or more, hundreds digit, tens
digit and ones digit are displayed by turns.
(Example) When 150 pulse;

0.5 secs. 0.5secs. 2 secs.

1

50

Shown as the outdoor capacity code.

Minute

Pulse

Code

display

32

33

SW2 setting

1ON23456

1

05

1ON23456

1ON23456

Display detail

Plate HEX liquid pipe temperature(TH6)
– 39~88

Explanation for display

– 39~88
(When the temperature is 0 or less, “–” and
temperature are displayed by turns.)

Unit



1ON23456

1ON23456

Condensing temperature(T

63HS

)

– 39~88

Caliculated maximum frequency
0~150

Water inlet temperature (TH32)
0~100

Requested capacity step(QSTEP)
0~7

– 39~88
(When the temperature is 0 or less, “–” and
temperature are displayed by turns.)

0~150
(When it is 100Hz or more, hundreds digit, tens
digit and ones digit are displayed by turns.
(Example) When 105Hz;

0.5 secs. 0.5secs. 2 secs.

0~100

0~7



Hz



Step

1ON23456

1ON23456

1ON23456

1ON23456

Ambient temperature (TH7)

-39~88

Outdoor heatsink temperature (TH8)

-40~200

Discharge superheat (SHd)
0~255

Cooling and Heating:SHd=TH4-T

Sub cool (SC)
0~130

Cooling:SC = T
Heating:SC = T

63HS-TH3
63HS-TH6

-39~88
(When the temperature is 0 or less, “–” and
temperature are displayed by turns.)

-40~200
(When the temperature is 0 or less, “–” and
temperature are displayed by turns.)
(When the thermistor detects 100 or more,
hundreds digit, tens digit and ones digit are
displayed by turns.)

0~255
(When the SHd is 100°C or more, hundreds
digit, tens digit and ones digit are displayed by
turns.)

63HS

0~130
(When the SC is 100°C or more, hundreds digit, tens
digit and ones digit are displayed by turns.)





°C

°C

SW2 setting

1ON23456

Display detail

Input current of outdoor unit
0~500

Explanation for display Unit

0~500
(When it is 100 or more, hundreds digit, tens digit
and ones digit are displayed by turns.)

0.1 A

1ON23456

1ON23456

1ON23456

LEV-B opening pulse
0~500

U9 error detail history(latest)

Direct current bus line voltage
150~400

0~500
(When it is 100 pulse or more, hundreds digit, tens
digit and ones digit are displayed by turns.)

Error details
(No error)
Over voltage
Insufficient

voltage
Input current

sensor error

ACTM error

150~400
(When it is 100V or more, hundreds digit, tens
digit and ones digit are displayed by turns.)

Cause

㧙

Power PCB

Power PCB

Control PCB

Control PCB

Code

00
01

02

04

20

Pulse

Code

display

V

1ON23456

1ON23456

1ON23456

1ON23456

Deferred error history (2)
of outdoor unit

Deferred error history (3)
of outdoor unit

Error code history (3) (Oldest)
Faulty unit number and error code are
displayed alternately.

Error thermistor display

When there is no error thermistor,
“–“ is displayed.

Deferred error code display
Blinking: being deferred
Lighting: deferment cancelled
“00” is displayed in case of no deferment.

Deferred error code display
Blinking: being deferred
Lighting: deferment cancelled
“00” is displayed in case of no deferment.

When no error history, “0” and “– –“ are displayed by
turns.

3: Liquid pipe thermistor (TH3)
3: Water inlet temp. thermistor (TH32)
6: Plate HEX liquid pipe thermistor (TH6)
7: Ambient temp.thermistor (TH7)
8: Heatsink thermistor (TH8)

Code

display

Code

display

Code

display

Code

display

34

35

SW2 setting

15

1ON23456

30

1

1ON23456

15

15

50

1

1ON23456

Display detail

Operation frequency when error occured.
0~225

Explanation for display Unit

0~225
(When it is 100Hz or more, hundreds digit, tens digit
and ones digit are displayed by turns.)
(Example) When 105Hz;

0.5 secs. 0.5secs. 2 secs.

1

05

Hz

1ON23456

1ON23456

1ON23456

Fan step when error occured.
0~10

LEV-A opening pulse when error
occured.
0~500

Water inlet temperature (TH32) when
error occured.
0~100

Plate HEX liquid pipe temperature(TH6)
when error occured.

-39~88

Condensing temperature when error
occured.

-39~88

0~10

0~500
(When it is 100 pulse or more, hundreds digit, tens
digit and ones digit are displayed by turns.)
(Example) When 130 pulse;

0.5 secs. 0.5secs. 2 secs.

0~100

-39~88
(When the temperature is 0°C or less, “–” and
temperature are displayed by turns.)
(Example) When –15°C;

0.5 secs. 0.5secs. 2 secs.

-39~88
(When the temperature is 0°C or less, “–” and
temperature are displayed by turns.)
(Example) When –15°C;

0.5 secs. 0.5secs. 2 secs.

Step

Pulse







1ON23456

1ON23456

1ON23456

Ambient temperature (TH7) when error
occured.

-39~88

Outdoor heatsink temperature (TH8)
when error occured.

-40~200

Discharge superheat (SHd) when error
occured.
0~255

Cooling and Heating :SHd=TH4-T

63HS

-39~88
(When the temperature is 0°C or less, “–” and
temperature are displayed by turns.)
(Example) When –15°C;

0.5 secs. 0.5secs. 2 secs.

-40~200
(When the temperature is 0°C or less, “–” and
temperature are displayed by turns.)
(When the temperature is 100°C or more, hundreds
digit, tens digit and ones digit are displayed by
turns.)

0~255
(When the temperature is 100°C or more, hundreds
digit, tens digit and ones digit are displayed by
turns.)
(Example) When 150°C;

0.5 secs. 0.5secs. 2 secs.







SW2 setting

15

1

1

05

Error details
(No error)
Over voltage
Insufficient

voltage
Input current

sensor error

ACTM error

Cause

㧙

Power PCB

Power PCB

Control PCB

Control PCB

Code

00
01

02

04

20

Display

Compressor frequency control

Input current restriction control
Compressor current restriction control

1
2



LED

1ON23456

Display detail

Sub cool (SC) when error occured.
0~130

Cooling:SC = T
Heating:SC = T

63HS-TH3
63HS-TH6

Explanation for display Unit

0~130
(When the temperature is 100°C or more, hundreds
digit, tens digit and ones digit are displayed by
turns.)
(Example) When 115°C;

0.5 secs. 0.5secs. 2 secs.



1ON23456

1ON23456

1ON23456

Compressor operation duration before
the unit stops with error.
0~999

Maximum frequency when
error occured.
0~150

Requested capacity step when error
occured.
0~7

Compressor frequency control status

0~999
(When it is 100 minutes or more, hundreds digit, tens
digit and ones digit are displayed by turns.)
(Example) When 415 minutes;

0.5 secs. 0.5secs. 2 secs.

4

0~150
(When it is 100Hz or more, hundreds digit, tens
digit and ones digit are displayed by turns.
(Example) When 105Hz;

0.5 secs. 0.5secs. 2 secs.

0~7

The following code will be a help to know the operat­ing status of unit.

•Ten place(left side):

15

Minute

Hz

Step

1ON23456

1ON23456

U9 Error details (To be shown while
error call is deferred.)

•First digit(Total figure of the corresponding relays are
displayed.)

Display

When the following 3 points are under control;
(1) Input current restriction control.
(2) Condensing temp.control(not to over rise).
(3) Heatsink temp.control(not to over rise).

Compressor frequency control

Discharge temp.control(not to over rise).

1

Condensing temp.control(not to over rise).

2

Freezing protection control

4

Heatsink temp.control(not to over rise).

8

36

Code

display

Code

display

37

8-8. FUNCTION OF SWITCHES

Switch

mark No. ON (with) OFF (without)

SW1

SW6

3~6 Model Setting 2

SW8

Function

1

2

3 No function
4 No function
5 No function
6 No function
1 Model Setting 1

2

1 Mode selection

2

3

Forced

defrosting

To clear error

history

Defrost control

selection

Cooling only,

Heating only or

Reversible

To fix operation

mode

ON to start Usual setting OFF

ON to clear Usual setting OFF

Do NOT use PUHZ-W90VHA
Do NOT use PUHZ-W90VHA
Do NOT use PUHZ-W90VHA
Do NOT use PUHZ-W90VHA
Do NOT use PUHZ-W90VHA

Energy saving

Cooling only or

Heating only

Cooling only Heating only OFF To fix as Cooling Only or Heating Only Always

<Important Note>
All these dip switches on PUHZ-W90VHA are set as shown above.
Spare PCBs, however, will be supplied without any settings, which means that all dip switches are switched OFF.
When servicing, please make sure to set all switches correctly, referring to the previous PCB which is removed from the unit.

For high

humidity

1=ON, 0=OFF

mode

Selection

Standard OFF

SW6
3456
1010

Powerful mode OFF – Always

Reversible OFF

Initial setting* Function details

Switch ON to forced defrosting When compressor

Switch ON to clear (erase) the followings:
(1)Error codes and Suspension flags in RAM
(2)Error codes and Suspension flags in

EEPROM
OFF
OFF
OFF
OFF
OFF

As shown in

the left table

PCB may be damaged, if switched ON.
Switch ON to change conditions (standard /

high himidity) to start defrosting

To select Cooling only, Heating only or
Reversible Always

––

–

Effective timing

(SW1, 8) /

Note (SW6)

is working in heating
mode.*1

off or operating

ON for other models

–

Make sure to set
SW6-3 to 6 correctly

*1. Forced defrosting should be done as follows.

Change the DIP SW1-1 on the outdoor controller board from OFF to ON.
Forced defrosting will start by the above operation  if these conditions written below are satisfied.

• Heat mode setting

• 10 minutes have passed since compressor started operating or previous forced defrosting finished.

• Pipe temperature is less than or equal to 8

.

• Forced defrosting will finish if certain conditions are satisfied.
Forced defrosting can be done if above conditions are satisfied when DIP SW1-1 is changed from OFF to ON.
After DIP SW1-1 is changed from OFF to ON, there is no problem if DIP SW1-1 is left ON or changed to OFF again. This
depends on the service conditions.

9

DISASSEMBLY PROCEDURE

PUHZ-W90VHA

OPERATING PROCEDURE

1. Removing the service panel and top panel

(1) Remove 3 screws (5x10) and slide the hook on the right

downward to remove the service panel.

(2) Remove screws (3 for front, 3 for rear/5x10) of the top

panel and remove it.

2. Removing the fan motor (MF1)

(1) Remove the service panel. (See figure 1.)
(2) Remove the top panel. (See figure 1.)
(3) Remove 5 screws (5x10) to detach the fan grille.

(See figure 1.)

(4) Remove a nut (for right handed screw of M6) to detach the

propeller. (See photo 1.)

(5) Disconnect the connector CNF1 on controller circuit board

in electrical parts box.

(6) Remove 4 screws (5x25) to detach the fan motor.

(See photo 2.)

Figure 1

Fan grille

Photo 1

Nut

PHOTOS&ILLUSTRATION

Top panel fixing screws

Slide

Grille fixing screws

Front panel

Propeller

Photo 2

Fan motor fixing screws

Top panel

Service panel

Service panel
fixing screws

Fan
motor
(MF1)

3. Removing the electrical box

(1) Remove the service panel. (See figure 1.)
(2) Remove the top panel. (See figure 1.)
(3) Disconnect the connecting wires from terminal block.

Remove all the following connectors from controller circuit board;

(4)

fan motor, linear expansion valve(x2), thermistor<Liquid pipe>,
thermistor<Discharge>, thermistor<Plate HEX Liquid>,
thermistor<Outdoor ambient>, high pressure sensor,
high pressure switch, four-way valve and bypass valve.
Then remove a screw (4x8) from the valve bed to remove
the lead wire.
Pull out the disconnected wire from the electrical parts box.
<Diagram symbol in the connector housing>

• Fan motor (CNF1)

• Linear expansion valve (LEV-A and LEV-B)

• Thermistor <Liquid pipe> (TH3)

• Thermistor <Discharge> (TH4)

• Thermistor <Plate HEX Liquid, Outdoor Ambient> (TH6/7)

• High pressure sensor (63HS)

• High pressure switch (63H)

• Solenoid valve coil <Four-way valve> (21S4)

• Solenoid valve coil <Bypass valve> (SV2)

(5) Remove the terminal cover and disconnect the compressor

lead wires.

(6) Remove a screw (4x10) and detach the electrical parts

box by pulling it upward. The electrical parts box is fixed
with 2 hooks on the left and 1 hook on the right.

Front panel fixing screws

Photo 3

Controller circuit board(C.B.)

Fan motor
fixing screws

Electrical parts box

Electrical parts box
fixing screw(4x10)

38

OPERATING PROCEDURE

PHOTOS&ILLUSTRATION

4. Removing the thermistor <Plate HEX Liquid> (TH6)

(1) Remove the service panel. (See figure 1.)
(2) Remove the top panel. (See figure 1.)
(3) Disconnect the connectors, TH6 and TH7 (red), on the

controller circuit board.
(4) Loosen the clamps for the lead wire.
(5) Pull out the thermistor <Plate HEX Liquid> (TH6) from

the sensor holder.

Note: In case of replacing thermistor <Plate HEX Liquid>
(TH6), replace it together with thermistor<Outdoor
ambient> (TH7), since they are combined together.

Refer to No.5 below to remove thermistor <Outdoor
ambient>.

5. Removing the thermistor <Outdoor ambient> (TH7)

(1) Remove the service panel. (See figure 1.)
(2) Remove the top panel. (See figure 1.)
(3) Disconnect the connector TH6 and TH7(red) on the

controller circuit board.
(4) Loosen the clamps for the lead wire.
(5) Pull out the thermistor <Outdoor ambient> (TH7) from

the sensor holder.

Note: In case of replacing thermistor <Outdoor ambient>
(TH7), replace it together with thermistor <Plate HEX

Liquid> (TH6), since they are combined together.

Refer to No.4 above to remove thermistor <Plate HEX

Liquid>.

Photo 4

Plate HEX liquid
thermistor(TH6)

Receiver

Photo 5

Sensor holder for outdoor ambient thermistor(TH7)

Outdoor liquid
thermistor(TH3)

Plate heat
exchanger

Plate heat exchanger
fixing screw

6. Removing the thermistor <Liquid pipe> (TH3) and
thermistor <Discharge> (TH4)

(1) Remove the service panel. (See figure 1.)
(2) Disconnect the connectors, TH3 (white) and TH4 (white),

on the controller circuit board.
(3) Loosen the clamps for the lead wire.
(4) Pull out the thermistor <Liquid pipe> (TH3) (See photo 4)

and thermistor <Discharge> (TH4) from the sensor holder.

7. Removing the thermistor <Inlet Water> (TH32)

(1) Remove the service panel. (See figure 1.)
(2) Remove 2 screws (5x10) and remove the front cover panel.

Remove 2 screws (5x10) and remove the back cover panel

(3)
(4) Disconnect the connectors, TH32 (black) on the controller

circuit board.
(5) Loosen the clamp for the lead wire.
(6) Remove the thermistor <Inlet water> (TH32) from the plate

heat exchanger.

Photo 6

Discharge
thermistor(TH4)

Photo 7

.

Note: Before removing the thermistor<Inlet water>(TH32),

recover water in the plate heat exchanger.

3939

Plate heat
exchanger

Inlet water
thermistor(TH32)

OPERATING PROCEDURE

PHOTOS&ILLUSTRATION

8. Removing the solenoid valve coil <Four-way valve> (21S4)
linear expansion valve coil (LEV (A), LEV (B)) and solenoid
valve coil <Bypass valve> (SV)

(1) Remove the service panel. (See figure 1.)
(2) Remove the top panel. (See figure 1.)
(3) Remove the electrical parts box. (See photo 3.)
[Removing the solenoid valve coil <Four-way valve> ]
(4) Remove solenoid valve coil <Four-way valve> fixing

screw(M4x6).
(5) Remove the solenoid valve coil <Four-way valve>.
(6) Disconnect the connector 21S4 (green) on the controller

circuit board.
[Removing the linear expansion valve coil]
(4) Remove the linear expansion valve coil by sliding the coil

upward.
(5) Disconnect the connectors, LEV A (white) and LEV B (red),

on the controller circuit board.
[Removing the solenoid valve coil <Bypass valve>]
(4) Remove the solenoid valve coil <Bypass valve> fixing

screw(M4x6).
(5) Remove the solenoid valve coil <Bypass valve> by sliding

the coil upward.
(6) Disconnect the connector SV2 (blue) on the controller cir-

cuit board.

9. Removing the four-way valve

(1) Remove the service panel. (See figure 1.)
(2) Remove the top panel. (See figure 1.)
(3) Remove the electrical parts box. (See photo 3.)
(4) Remove 3 stay fixing screws (4x10) and remove the stay.
(5) Remove 3 right side panel fixing screw (5x10) in the rear

of the unit and remove the right side panel.
(6) Remove the solenoid valve coil <Four-way valve>.

(See photo 8.)
(7) Recover refrigerant.
(8) Remove the welded part of four-way valve.

Photo 8

Solenoid
valve coil(21S4)

High pressure
switch

Photo 9

Solenoid
valve coil(21S4)

Four-way valve

Solenoid
valve coil(SV)

LEV-A

LEV-B

Bypass valve

Note 1: Recover refrigerant without letting it out in the air.
Note 2: The welded part can be removed easily by
removing the right side panel.
Note 3: When installing the four-way valve, make sure to

cover it with a wet cloth to prevent it from heating
(120°C or more), then braze the pipes so that the
inside of pipes are not oxidized.

10

. Removing linear expansion valve

(1) Remove the service panel. (See figure 1.)
(2) Remove the top panel. (See figure 1.)
(3) Remove the electrical parts box. (See photo 3.)
(4) Remove 3 stay fixing screws (4x10) and remove the stay.
(5) Remove 3 right side panel fixing screw (5x10) in the rear

of the unit and then remove the right side panel.
(6) Remove the linear expansion valve.
(7) Recover refrigerant.
(8) Remove the welded part of linear expansion valve.

Note 1: Collect refrigerant without spreading it in the air.
Note 2: The welded part can be removed easily by
removing the back panel.
Note 3: When installing the linear expansion valve, cover

it with a wet cloth to prevent it from heating
(120°C or more), then braze the pipes so that the
inside of pipes are not oxidized.

Stay fixing screw

Stay fixing
screw

Stay fixing
screw

Four-way valve

40

41

OPERATING PROCEDURE

PHOTOS&ILLUSTRATION

11. Removing the bypass valve

(1) Remove the service panel. (See figure 1.)
(2) Remove the top panel. (See figure 1.)
(3) Remove the electrical parts box. (See photo 3.)
(4) Remove 3 right side panel fixing screws (5x10) in the rear

of the unit and remove the right side panel.
(5) Remove the bypass valve solenoid coil.
(6) Recover refrigerant.
(7) Remove the welded part of bypass valve.

Note 1: Recover refrigerant without letting it out in the air.
Note 2: The welded part can be removed easily by

removing the right side panel.

12

. Removing the high pressure switch (63H)

(1) Remove the service panel. (See figure 1.)
(2) Remove the top panel. (See figure 1.)
(3) Remove the electrical parts box. (See photo 3.)
(4) Remove 3 right side panel fixing screws (5x10) in the rear

of the unit and remove the right side panel.
(5) Pull out the lead wire of high pressure switch.
(6) Recover refrigerant.
(7) Remove the welded part of high pressure switch.

Note 1: Recover refrigerant without letting it out in the air.
Note 2: The welded part can be removed easily by

removing the right side panel.
Note 3: When installing the high pressure switch, make

sure to cover it with a wet cloth to prevent it from
heating (120°C or more), then braze the pipes so
that the inside of pipes are not oxidized.

Photo 10

Solenoid
valve coil(21S4)

High pressure
switch

Four-way valve

Solenoid
valve coil(SV2)

LEV-A LEV-B

Bypass valve

13

. Removing the high pressure sensor (63HS)

(1) Remove the service panel. (See figure 1.)
(2) Remove the top panel. (See figure 1.)
(3) Remove the electrical parts box. (See photo 3.)
(4) Remove 3 right side panel fixing screws (5x10) in the rear

of the unit and remove the right side panel.

(5) Pull out the lead wire of high pressure sensor.
(6) Recover refrigerant.
(7) Remove the welded part of high pressure sensor.

Note 1: Recover refrigerant without letting it out in the air.
Note 2: The welded part can be removed easily by
removing the right side panel.
Note 3: When installing the high pressure switch, make

sure to cover it with a wet cloth to prevent it from
heating (120°C or more), then braze the pipes so
that the inside of pipes are not oxidized.

OPERATING PROCEDURE

PHOTOS&ILLUSTRATION

14. Removing the compressor (MC)

(1) Remove the service panel. (See figure 1.)
(2) Remove the top panel. (See figure 1.)

Remove 2 screws (5x10) and remove the front cover panel.

(3)
(4)

Remove 2 screws (5x10) and remove the back cover panel.

(5) Remove the electrical parts box. (See photo 3.)

Remove 3 screws (4x10) and remove the stay. (See photo 9.)

(6)
(7) Remove 3 screws (5x10) in the rear of the unit and remove

the right side panel.

(8) Remove 5 screws (1:4x10 4:5x10) and remove the front

panel.
(9) Remove 3 screws (4x10) and remove the separator.
(

10

) Remove the terminal cover and remove the lead wire for

compressor.

11

) Remove the soundproof cover for compressor.

(

12

) Recover refrigerant.

(

13

) Remove the 3 points of the compressor fixing nut using a

(

spanner or a adjustable wrench.

14

) Remove the welded pipe of the compressor, then remove

(

the compressor.

Note 1: Recover refrigerant without letting it out in the air.

15

. Removing the receiver

(1) Remove the service panel. (See figure 1.)
(2) Remove the top panel. (See figure 1.)

Remove 2 screws (5x10) and remove the front cover panel.

(3)
(4)

Remove 2 screws (5x10) and remove the back cover panel.
(5) Remove the electrical parts box. (See photo 3.)

Remove 3 screws (4x10) and remove the stay. (See photo 9.)

(6)
(7) Remove 3 screw (5x10) in the rear of the unit and remove

the right side panel.
(8) Recover the refrigerant.
(9) Remove 2 welded pipes of receiver.
(

10

) Remove 2 receiver leg fixing screws (4x10), then remove

the receiver.

Photo 11

Compressor
(MC)

Photo 12

Terminal cover

Receiver

Sound proof
cover for
compressor

Lead wire for compressor

Note 1: Recover refrigerant without letting it out in the air.

16. Removing the plate heat exchanger

(1) Remove the service panel. (See figure 1.)
(2) Remove the top panel. (See figure 1.)

Remove 2 screws (5x10) and remove the front cover panel.

(3)
(4)

Remove 2 screws (5x10) and remove the back cover panel.
(5) Remove the electrical parts box. (See photo 3.)

Remove 3 screws (4x10) and remove the stay. (See photo 9.)

(6)
(7) Remove 3 screw (5x10) in the rear of the unit and remove

the right side panel.
(8) Recover the refrigerant
(9) Remove 2 welded pipes of plate heat exchanger inlet and

outlet.
(

10

) Remove 2 plate heat exchanger fixing screws (4x10),

then remove the plate heat exchanger.

Note 1: Recover refrigerant without letting it out in the air.
Note 2:Before removing the thermistor <Inlet water>(TH32),

recover water in the plate heat exchanger.

Compressor
fixing nut

Photo 13

Plate HEX liquid
thermistor(TH6)

Receiver

Receiver
leg fixing
screw

Outdoor liquid
thermistor(TH3)

Plate heat
exchanger

Plate heat exchanger
fixing screw

42

43

OPERATING PROCEDURE

17. Removing the interface circuit board (I.F.) : Figure 2

(1) Remove 2 Interface board cover fixing screws (4x10).
(2) Remove all lead wire connectors (CNIF1, CNIF2, CNIF3,

CNIF4) on interface circuit board (I.F.).

(3)

Remove interface circuit board from the C.B. base.(5 supports)

18. Removing the controller circuit board (C.B.) : Figure 2

(1)

Remove all lead wire connectors on controller circuit board (C.B.).
CNF1,CNDC,CNAC,CN2,CN4,CN52C,CN3S,CNDM,CN51

21S4,SV2,63H,63HS,LEV-A,LEV-B,

TH32,TH7/6,TH3,TH4

(2)

Remove controller circuit board from the C.B. base.(5 supports)

19.

Removing the noise filter circuit board (N.F.) : Figure 2, Photo 14

(1) Remove E2,CN5,LO,NO lead wire connectors from noise

filter circuit board (N.F.).
(2) Remove E1 lead wire connector from electrical parts box.
(3)

Remove L, N lead wire connectors from terminal block (TB1).
(4) Remove 4 screws (4x10) for fixing the C.B. base and

detach the C.B. base from the electrical parts box.
(5) Remove CNAC1, CNAC2, E1, LI, NI lead wire connectors

from noise filter circuit board (N.F.).
(6) Remove noise filter circuit board from the C.B. base.

(11 supports)

20.

Removing the power circuit board (P.B.) : Figure 2, Photo 15

(1) Remove CN2, CN4, CNDC lead wire connectors from con

troller circuit board (C.B.).
(2) Remove LO, NO, CN5 lead wire connectors from noise

filter circuit board (N.F.).
(3)

Remove 4 screws(4x10) for fixing the C.B. base and detach

the C.B. base from the electrical parts box.
(4)

Remove all lead wire connectors on power circuit board (P.B.).

CNAF, CN2, CN3, CN5, CN4, CNDC

TABU, TABV ,TAVW, TABT, TABS, TABP1, TABN1, TABN2
(5)

Remove power circuit board from the electrical parts box.

(3 supports and 4 screws ( 2 screws (3x12) + 2screws

(4x18))

21.

Removing the active filter module (ACTM) : Figure 2, Photo15

(1) Remove CN2, CN4, CNDC lead wire connectors from con

troller circuit board (C.B.).
(2) Remove LO, NO, CN5 lead wire connectors from noise

filter circuit board (N.F.).
(3)

Remove 4 screws (4x10) for fixing the C.B. base and detach

the C.B. base from the electrical parts box.
(4)

Remove all lead wires on active filter module (ACTM).

L1, L2, P, Io, +, -, CNAF (4 wires)
(5)

Remove the active filter module (ACTM) from the electrical

parts box.(2 screws (4x14))

22. Removing the reactor (DCL) : Figure 2, Photo16

(1) Remove 4 reactor fixing screws (4x16) to detach the reac

tor (DCL).
(2) Disconnect L1,L2 lead wire from active filter module

(ACTM).Remove reactor wire from wire supoort.

23. Removing the thermistor <HEATSINK> (TH8) : Photo 15

(1) Remove CN2, CN4, CNDC lead wire connectors from con

troller circuit board (C.B.).
(2) Remove LO, NO, CN5 lead wire connectors from noise

filter circuit board (N.F.).
(3)

Remove 4 screws(4x10) for fixing the C.B. base and detach

the C.B. base from the electrical parts box.
(4)

Remove all lead wire connectors on power circuit board (P.B.).

CNAF,CN2,CN3,CN5,CN4,CNDC

TABU,TABV,TAVW,TABT,TABS,TABP1,TABN1,TABN2

Remove power circuit board from the electrical parts box.

(5)

(3 supports and 4 screws( 2 screws(3x12) + 2screws(4x18))
(6) Remove the thermistor<HEATSINK> from the electrical

parts box. (1 screw(3x12)

Figure 2

Electrical
parts box

Controller
circuit board
(C.B.)

Photo 14

-

Photo 15

-

Lead wire
for heatsink
thermistor

-

Photo 16

-

PHOTOS&ILLUSTRATION

Active filter module (ACTM)

Power curcuit board (P.B.)

Noise filter circuit
board (N.F.)

Noise filter circuit board (N.F.)

Active filter module(ACTM)

(TB1)

Reactor(DCL)

Power circuit board
(P.B)

Wire supportTerminal block

Reactor (DCL)

C.B. base

Interface circuit
board (I.F.)

HEAD OFFICE : TOKYO BLDG., 2-7-3, MARUNOUCHI, CHIYODA-KU, TOKYO 100-8310, JAPAN

©Copyright 2007 MITSUBISHI ELECTRIC ENGINEERING CO., LTD.
Distributed in Aug. 2007 No. OCH419 PDF 8
Made in Japan

New publication, effective Aug. 2007
Specifications subject to change without notice.