Mitsubishi Electric PUHZ-W90VHA User manual

SERVICE MANUAL
AIR TO WATER HEAT PUMP
No. OCH419
CONTENTS
1. SAFETY PRECAUTION ..........................................2
2. SPECIFICATIONS ..................................................... 4
3. DATA .............................................................................5
4. OUTLINES AND DIMENSIONS............................7
5. WIRING DIAGRAM ...................................................8
6. WIRING SPECIFICATIONS....................................9
7. REFRIGERANT SYSTEM DIAGRAM...................10
8. TROUBLESHOOTING ...........................................11
9. DISASSEMBLY PROCEDURE ...........................38
August 2007
Note:
•This manual describes only
service data of PUHZ-W90VHA.
•RoHS compliant products have
<G> mark on the spec name plate.
R410A
[model name]
PUHZ-W90VHA
[Service Ref.]
PUHZ-W90VHA
PUHZ-W90VHA
PARTS CATALOG (OCB419)

2
SAFETY PRECAUTION
1
Cautions for units utilizing refrigerant R410A
1-2. CAUTIONS RELATED TO NEW REFRIGERANT
1-1. ALWAYS OBSERVE FOR SAFETY
Before obtaining access to terminal, all supply ciucuits must be disconnected.
[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.)
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.
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.
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.
Electronic refrigerant
charging scale
Vacuum pump adaptor
Gauge manifold
Torque wrench
Gas leak detector
Charge hose
Tools for R410A
Ventilate the room if refrigerant leaks during operation. If refrigerant comes into contact with
a flame, poisonous gases will be released.

33
1-3. CAUTIONS FOR REFRIGERANT PIPING WORK
Tools for R410A (The following table shows whether conventional tools can be used or not.)
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 thermis-
tor vacuum gauge and
vacuum valve
Charging cylinder
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 refri-
gerant 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 adop-
ter 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
Tools and materials Use R410A tools Can R22 tools be used?
(Usable if equipped
with adopter for rever-
se flow)
Can R407C tools be used?
(Usable if equipped
with adopter for rever-
se flow)
: 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.
Gravimeter
Unit
[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 specifications. (UNF1/2)
·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

4
SPECIFICATIONS
2
Power supply Phase 㱢
Voltage V
noitidnocgnitarepolanimoNzHycneuqerF
Heating Capacity kW Heating(A2/W35)
(A2/W35) 2+)blub-yrD(erutarepmetriaedistuOPOC 㷄
1+)blub-teW(erutarepm
etriaedistuOWktupnirewoP 㷄
53+/03+)teltuo/telni(erutarepmetretaWnim/LwolfretawlanimoN 㷄
Heating Capacity kW Heating(A7/W35)
(A7/W35) 7+)blub-yrD(e
rutarepmetriaedistuOPOC 㷄
6+)blub-teW(erutarepmetriaedistuOWktupnirewoP 㷄
53+/03+)teltuo/telni(erutarepme
tretaWnim/LwolfretawlanimoN 㷄
Cooling Capacity kW Cooling(A35/W7)
(A35/W7) EER (COP) Outside air temperature (Dry-bulb) +35㷄
42+)blub-teW(erutarepmetriaedistuOWktupnirewoP 㷄
7+/21+)teltuo/telni(erutarepmetretaWnim/Lwolfretawla
nimoN 㷄
Cooling Capacity kW Cooling(A35/W18)
(A35/W18) EER (COP) Outside air temperature (Dry-bulb) +35㷄
42+)blub-teW(erutarepmetriaedistuOWktupnirewoP 㷄
81+/32+)teltuo/telni(erutarepmetretaWnim/Lwolfretawl
animoN 㷄
regnahcxetaehetalPtinuroodtuO
Model name ALFA LAVAL
Running current Heating(A7/W35) 04-03HCAA
Cooling(A35/W7) A
mm4.04:AAtnerruc.xaM
mm2.862:BgnisacretuO
External finish
mm39:WlortnoctnaregirfeR
mm523:HrosserpmoC
mm96:DledoM
setalp0
4WktuptuorotoM
Start type
Protection devices
erutarepmetretawteltuomumixaML)ledoM(liO
WretaehesacknarC
Heat exchanger (Air)
(Water)
Fan Fan(drive)×No.
Fan motor output kW
Air flow m3/min
(CFM)
Defrost method
Noise level Heating dB
Cooling dB
Dimensions Width mm(in.)
Depth mm(in.)
Height mm(in.)
)sbl(gkthgieW
Refrigerant
Quantity kg(lbs) *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.
Guaranteed operating Heating 㷄
range (Outdoor) Cooling 㷄
nim/LwolfretaW 10.0 䌾25.8
PUHZ-W90VHA
950 (37-3/8)
330 +30*1 (13+1-3/16)
0.67 (FV50S)
Reverse cycle *3
49 *2
49 *2
Discharge thermo
䊷
1.3
Line start
HP switch
943 (37-1/8)
Propeller fan × 1
0.060
55
(1,940)
-20 䌾+35
Galvanized plate
10.3
15.7
23.0
Munsell 3Y 7.8/1.1
Linear expansion valve
Hermetic twin rotary
Plate fin coil
Plate heat exchanger
-5*4 䌾+46
R410A
2.4 (5.3)
1
230
50
2.06
25.8
9.0
3.90
79 (174)
7.0
3.40
2.31
25.8
7.1
2.00
7.1
20.4
TNB220FLHM1
3.70
1.92
3.55
20.4
w
H
D
Water IN
Ref.OUT
(Heating)
Ref.IN
(Heating)
Thermistor
(TH32)
Water OUT
B
A
Ambient temperature []
-20 -15
65
60
55
50
45
40
-10 -5 0 5 10
Maximum outlet water temptemperature [
]

5
DATA
3
1.5m
1m
MICROPHONE
UNIT
GROUND
90
80
70
60
50
40
30
20
10 63 125 250 500 1000 2000 4000 8000
APPROXIMATE
THRESHOLD OF
HEARING FOR
CONTINUOUS
NOISE
NC-60
NC-50
NC-40
NC-30
NC-20
NC-70
BAND CENTER FREQUENCIES, Hz
PUHZ-W90VHA
COOLING
MODE
HEATING
49
SPL(dB)
49
LINE
OCTAVE BAND SOUND PRESSURE LEVEL, dB (0 dB = 0.0002 bar)
3-1. NOISE CRITERION CURVES

6
3-2. STANDARD OPERATION DATA
Mode Cooling (A35/W7) Heating (A7/W35)
Total
Capacity W 7,100 9,000
Input kW 3.55 2.31
Electrical circuit
Outdoor unit PUHZ-W90VHA
Phase, Hz 1, 50
Voltage V 230
Current A 15.7 10.3
Refrigerant circuit
Discharge pressure MPa 2.74 2.21
Suction pressure MPa 0.73 0.64
Discharge temperature 74 65
Condensing temperature 47 38
Suction temperature 3-1
Water
conditions
Flow volume L/min 20.4 25.8
Outlet water temperature 735
Outdoor
conditions
Intake air temperature
D.B. 35 7
W.B. 24 6
The unit of pressure has been changed to MPa based on international SI system.
The conversion factor is : 1(MPa)=10.2(kgf/cm2)

77
OUTLINES AND DIMENSIONS
4
PUHZ-W90VHA
Handle for moving
Side Air Intake
330
175 600 175
53
28 370 19
417
Installation Feet
2-U Shaped notched holes (Foundfation Bolt M10)
Side Air Intake
Rear Air Intake
Air Discharge
2-12×36 oval holes (Foundation Bolt M10)
30
81 219
30 220 145 145 145
Drain hole (5-:33)
119 40
34
Front cover
Rear cover
Power supply wiring hole (2-:27Knock Out)
see Detail
Unit : mm
39
24
26998
ISO 228/1-G1 B
Detail Scale 1:3
57
Air Intake
Rear Air Intake
Handle for moving
Handle for moving
Water OUT
Water IN
682
943
950
322
23
473
Terminal Connections
Left······Power supply wiring Right······Controller wiring
Service panel Handle for moving
Handle for moving
1 FREE SPACE (Around the unit) 2 SERVICE SPACE 3 FOUNDATION BOLTS
Less than
Over
500
Over
500
The diagram below shows a basic example. Explantion of particular details are given in the installation manuals etc.
Over300
Over10
Service space
Dimensions of space needed for service access are shown in the below diagram.
30
<Foundation bolt height>
Please secure the unit firmly with 4 foundation (M10) bolts. (Bolts and washers must be purchased locally.)
Over 10mm
Over 10mm
Over 300mm
Over 00mm
(4''
FOUNDATION

8
WIRING DIAGRAM5
PUHZ-W90VHA
TB1
MC
MF1
21S4
63H
TH3
TH4
TH6
TH7
TH8
LEV-A, LEV-B
DCL
Terminal Block<Power Supply>
TB2 Terminal Block<Controller>
TB3 Terminal Block<Controller>
Motor for Compressor
Fan Motor
Solenoid Valve<Four-Way Valve>
High Pressure Switch
63HS High Pressure Sensor
SV Solenoid Valve<Bypass Valve>
Thermistor<Liquid>
Thermistor<Discharge>
Thermistor<Plate HEX Iiquid>
Thermistor<Ambient>
Thermistor<Heatsink>
TH32 Thermistor<Inlet water>
Electronic Expansion Valve
Reactor
ACTM Active Filter Module
Power Circuit Board
Connection Terminal<U/V/W-Phase>
P.B.
TABS/T
Noise Filter Circuit Board
Connection Terminal<L-Phase>
Connection Terminal<Ground>
N.F.
LI,LO
Connection Terminal<N-Phase>
NI,NO
EI,E2
Controller Circuit Board
Switch<Function Switch>
Switch<Function Switch>
Switch<Function Switch>
SW1
SW2
SW6
SW8
LED3 LED<Operation/Inspection Indicators>
C.B.
Interface Circuit Board
I.F.
TABP1/P2
Power ModuleIPM
Diode bridgeDS2, DS3
52C Relay
52C
SYMBOL NAME SYMBOL NAME
Connection Terminal<L/N-Phase>
Connection Terminal<DC Voltage>
TABN1/N2 Connection Terminal<DC Voltage>
TABU/V/W
Switch<Model Select>
Relay
Fuse<T6.3AL250V>
F3, F4
X52, X55
SYMBOL NAME
MS
3~
MF1
M
1
3
1
7
34 11121
1
1
6
5
7
3
1
1
17
2
CNF1
(WHT)
TRANS
CNDC
(PNK)
TH7/6
(RED)
TH3
(WHT)
TH4
(WHT)
TH7
t° t° t° t°
TH6 TH3 TH4
12
TH32
(BLK)
t°
TH32 63HS
63HS
(WHT)
31
CNS
(WHT)
63H
(YLW)
3
1
63H
CNIF1
(RED)
CNIF2
(WHT)
CNIF3
(WHT)
CNIF4
(WHT)
C. B.
P. B.
N. F.
SW6
SW1
SW8
SW2
LED3
2
22
6
6
3
5
3
3
7
I. F.
CN2
(WHT)
F3
12 12
1313
13
2
71
1
2
1
2
1
2
7
6
CNAC
(WHT)
CN4
(WHT)
12
34
F4 21S4
(GRN)
SV2
(BLU)
X52 X55
21S4 SV
2
2
LN
CNDC
(PNK)
DS2
DS3
TABN
TABP
IPM
U
TABP2
TABV
TABW
TABN2
TABN1
TABS
TABP1
TABT
TABU
MS
3~
UVW
MC
CN2
(WHT)
41
CNAF
(WHT)
CN4
(WHT)
CN5
(RED)
CN3
(WHT)
RED
RED
WHT WHT
WHT
WHT
BLK
BLK
BLK
BLU
BLU
RED
BLU
YLW/GRN
BLK
TH8
t°
1613
15
CNVMNT
(WHT)
CNMNT
(WHT)
LEV-A
(WHT)
LEV-A
1
5
CN51
(WHT)
1
3
CNDM
(WHT)
1
3
CN3S
(RED)
DCL
ACTM
L1
LO
52C
NO
LI NI
CN5
(RED)
L2
N2
Io
N1
P
4
16
RED
BLK
RED
WHT
RED
BLU
CNAC2
(RED)
CNAC1
(WHT)
CN52C
(BLK)
WHT
2
2
1
3
E2
EI
U
U
1
2
3
5
1
2
3
1
TB1 A2 A3 A4
RED
RED
TB2
CONTROLLER
POWER SUPPLY
~/N 230V 50Hz
A1
YLW
ORN
BRN
B1 B2 B3
PNK
TB3
A5
M
61
LEV-B
(RED)
CN52C
(RED)
LEV-B
BLU
WHT
001010
123456
SW6
*1 MODEL SELECT
*1
1=ON, 0=OFF

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
Wiring
Wire No. ×
size (mm2)
Outdoor unit power supply, earth 3 × Min.4
Controller-Outdoor unit *2 8 × Min.0.5 (polar)
Circuit
rating
Outdoor unit L-N (single) AC 230 V
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.

10
REFRIGERANT SYSTEM DIAGRAM7
Distributor
TH7
Strainer(#100) Strainer(#100)
Receiver
LEV-B
TH6
TH32
Plate HEX
Water IN
Water OUT
Strainer
(#100)
TH3
CHECK/V
CHECK/V CHECK/V
H/P SW
TH4
TH8 P/B
LEV-A
COMP
REV/V
P-Sensor
S/V
Strainer
(#100)
Refrigerant flow in heating
Refrigerant flow in cooling
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
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
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
Symbol Part name Detail
PUHZ-W90VHA

11
TROUBLESHOOTING8
Unit conditions at service Error code Actions to be taken for service (summary)
The trouble is reoccurring.
Displayed
Not displayed
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.
The trouble is not reoccurring.
Logged
Not logged
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.
<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.
8-1. TROUBLESHOOTING
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.)

12
8-3. SELF-DIAGNOSIS ACTION TABLE
<Abnormalities detected when the power is turned on>
Error Code
Abnormal point and detection method
Case Judgment and action
None —
No voltage is supplied to terminal
block(TB1) of outdoor unit.
a) Power supply breaker is
turned off.
b) Contact failure or disconnec-
tion of power supply
terminal
c) Open phase (L or N phase)
Electric power is not supplied
to power supply terminal of
noise filter circuit board / out-
door power circuit board.
a) Contact failure of power
supply terminal
b) Open phase on the noise
filter circuit board / outdoor
power circuit board
: Disconnection of terminal
LI, NI, LO, NO
: Disconnection of terminal
TABT or TABS
Electric power is not supplied to
outdoor controller circuit board.
a) Connector disconnected
(CNDC)
Disconnection of reactor (DCL)
Disconnection of outdoor noise
filter circuit board or parts fail-
ure in outdoor noise filter circuit
board
Defective outdoor power circuit
board
Defective outdoor controller
circuit board
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.
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.)
F5
63H connector open
Abnormal if 63H connector circuit is open
for 3 minutes continuously from being
switched on.
63H: High-pressure switch
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 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.

13
<Abnormalities detected while unit is operating>
Error Code
Abnormal point and detection method Judgment and action
U1
High pressure (High-pressure switch
63H activated)
Abnormal if high-pressure switch 63H is
activated ( +) during compressor opera-
tion.
+4.15 MPa
63H: High-pressure switch
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
~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.
Case
U2
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.
Overheated compressor
operation caused by insufficient
refrigerant
Defective thermistor
Defective outdoor controller
board
Defective operation of linear
expansion valve
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.
U3
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 defrost-
ing.)
Disconnection or contact
failure of connector (TH4) on
the outdoor controller circuit
board.
Defective thermistor
Defective outdoor controller
circuit board
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.

14
Thermistors Open detection Short detection
Symbol Name
TH3
TH6
TH7
TH8
– 40or below
– 40or below
– 40or below
– 40or below
– 35or below
90or above
90or above
90or above
102or above
102or above
Thermistor <Liquid temperature>
Thermistor <Inlet water temperature>
Thermistor <Plate HEX liquid temperature>
Thermistor <Ambient temperature>
Thermistor <Heatsink temperature>
TH32
Error Code
Abnormal point and detection method
Case Judgment and action
U5
Temperature of heatsink
Abnormal if heatsink thermistor(TH8)
detects temperature indicated 77.
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
 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.
U4
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.)
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 tempera-
ture on LED display.
(Thermistor/TH3,TH32,TH6,TH7,TH8: Refer
to 8-5.)
(SW2 : Refer to 8-7)
Replace outdoor controller circuit board.
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
()
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
Replace outdoor power circuit board.
Check facility of power supply.
Correct the wiring (U•V•W phase) to
compressor. Refer to 8-6 (Outdoor power
circuit board).
Check compressor referring to 8-4.

15
Error Code
Abnormal point and detection method
Case Judgment and action
U7
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 com-
pressor starts operating for 10 minutes.
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
 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
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.
Failure in the operation of
the DC fan motor
Failure in the outdoor circuit
controller 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.)
U9
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.
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 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.
UF
Compressor overcurrent interruption
(When compressor locked)
Abnormal if overcurrent of DC bus or
compressor is detected within 30 seconds
after compressor starts operating.

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 facility of power supply.
Correct the wiring (U
•
V
•
W phase) to
compressor.
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.
Ud
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.
Defective outdoor fan (fan
motor) or short cycle of out-
door unit during cooling opera-
tion
Defective outdoor pipe
thermistor (TH3)
Defective outdoor controller
board
Defective pressure sensor
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.)

16
Error Code
Abnormal point and detection method Judgment and action
Case
UH
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.
Disconnection of compresso
wiring
Defective circuit of current
sensor on outdoor power
circuit board
Decrease of power supply volt-
age
Correct the wiring (U•V•W phase) to com-
pressor. Refer to 8-6 (Outdoor power circuit
board).
Replace outdoor power circuit board.
Check the facility of power supply.
UP
Compressor overcurrent interruption
Abnormal if overcurrent DC bus or com-
pressor is detected after compressor starts
operating for 30 seconds.

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
Check facility of power supply.
Correct the wiring (U•V•W phase) to com-
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.
Ed
Serial communication error
Abnormal if serial communication
between outdoor controller circuit
board and outdoor power circuit board
is defective.
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 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.

17
Error Code
Abnormal point and detection method Judgment and action
Case
P6
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
-2or lower and compressor operation
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 oper-
ation frequency is less than or equal to
30 Hz. Detection is inoperative during
defrosting.
<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
Overcharge of refrigerant
Defective refrigerant circuit
(clogs)
Malfunction of linear expansion
valve
<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.
 Check operating condition of refrigerant
circuit.
Check linear expansion valve.
P8
UE
Abnormal pressure of pressure sensor
(63HS)
Abnormal if pressure sensor(63HS) detects
0.1MPa or less.
Detection is inoperative for 3 minutes after
compressor starting and 3minutes after
and during defrosting.
Disconnection or contact
failure of connector (63HS)
on the outdoor controller
circuit board
Defective pressure sensor
Defective outdoor controller
circuit board
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.
Pipe temperature
Abnormal if the following conditions are
detected for continuously 3 minutes after
compressor starts operating for 10 minutes.
1.Cooling mode
T63HS-TH72and
TH3-TH74or T63HS-TH3< 0and
TH32-TH60and
Compressor operation frequency is 61Hz or more.
2.Heating mode
T63HS-TH322and
TH6-TH321and
TH7-TH31and
Compressor operation frequency is 61Hz or more.
T63HS:Condensing temperature of pressure
sensor(63HS)
Thermistor
TH3:Liquid temperature
TH32:Inlet water temperature
TH6:Plate HEX Liquid temperature
TH7:Ambient temperature
Leakage or shortage of
refrigerant
Malfunction of linear
expansion valve
Refrigerant circuit is clogged
with foreign objects.
+Clogging occurs in the parts
which become below freezing
point when water enters in
refrigerant circuit.
Disconnection holder of
thermistor
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.
Ambient temperature (TH7)
-19
stage-g
stage-f
stage-e
stage-d
stage-c
stage-b
stage-a
-18 -16 -15 -13 -12 -11 -10 -8 -7 -3 -2
[]
Tcond
Tcond 63 61 59 57 54 51 48
stage-a stage-b stage-c stage-d stage-e stage-f stage-g

18
Error Code
Abnormal point and detection method Judgment and action
Case
PE
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
Reduced water flow
· Clogged filter
· Leak of water
Low temperature
· Low-load
· Low temperature inlet water
Defective water pump
Leakage or shortage of
refrigerant
 Check water piping.
Check water pump.
Check intake superheat.
Check leakage of refrigerant.

19
8-4. HOW TO CHECK THE PARTS
PUHZ-W90VHA
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

20
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 board and fan motor.)
Self check
Symptom : The outdoor fan does not run.


Check method of DC fan motor (fan motor / outdoor controller circuit board)
No
Wiring contact check
Contact of fan motor connector (CNF1)
Wiring recovery
END
END
Replace fan motor.
Replace outdoor controller circuit board.
Replace outdoor control circuit board.
Replace outdoor control circuit board.
Replace fan motor.
Replace fan motor.
Check fan motor rotation.
Check fan motor rotation.
Is the voltage normal?
Is the fuse normal?
Is there no contact failure?
Check fuse (F5) on outdoor control
circuit board.
Yes
No
No
Yes
Yes
Power supply check
Measure the voltage on the outdoor controller circuit. (The connector CNF1 is removed.)
TEST POINTVDC DC280-330V (between 1 (+) and 4 (-) of CNF1)
VDC DC15V (between 5 (+) and 4 (-) of CNF1)
NG
OK
NG
OK