Mitsubishi Electric PUHZ-SW40VHA User manual

SERVICE MANUAL No.OCH525
SPLIT-TYPE, HEAT PUMP AIR CONDITIONERS
R410A
October 2012
Outdoor unit
[Model name]
PUHZ-SW40VHA
PUHZ-SW50VHA
[Service Ref.]
PUHZ-SW40VHA
PUHZ-SW50VHA
PARTS CATALOG (OCB525)
CONTENTS
1 REFERENCE MANUAL··································2
2 SAFETY PRECAUTION··································2
3 FEATURES······················································6
4 SPECIFICATIONS···········································6
5 DATA································································8
6 OUTLINES AND DIMENSIONS······················9
7 WIRING DIAGRAM ·······································10
8 WIRING SPECIFICATIONS··························· 11
9 REFRIGERANT SYSTEM DIAGRAM ··············12
10 TROUBLESHOOTING···································14
11 DISASSEMBLY PROCEDURE······················55
Note:
•This manual describes only
service data of the outdoor
units.
Salt proof model
PUHZ-SW40VHA-BS
PUHZ-SW50VHA-BS
PUHZ-SW40VHA-BS
PUHZ-SW50VHA-BS

2
2-1. ALWAYS OBSERVE FOR SAFETY
Before obtaining access to terminal, all supply circuits must be disconnected.
2SAFETY PRECAUTION
2-2. CAUTIONS RELATED TO NEW REFRIGERANT
Cautions for units utilizing refrigerant R410A
1REFERENCE MANUAL
Preparation before the repair service.
• Prepare the proper tools.
• Prepare the proper protectors.
• Provide adequate ventilation.
• After stopping the operation of the air conditioner, turn off
the power-supply breaker.
• Discharge the condenser before the work involving
the electric parts.
Precautions during the repair service.
• Do not perform the work involving the electric parts
with wet hands.
• Do not pour water into the electric parts.
• Do not touch the refrigerant.
• Do not touch the hot or cold areas in the refrigerating cycle.
• When the repair or the inspection of the circuit needs to be
done without turning off the power,
exercise great caution not to touch the live parts.
Use new refrigerant pipes. Make sure that the inside and outside of refrige-
rant piping is clean and it has no contaminants
such as sulfur, oxides, dirt, shaving particles, etc,
which are hazard to refrigerant cycle.
In addition, use pipes with specified thickness.
In case of using the existing pipes for R22, be careful with
the followings.
· Be sure to clean the pipes and make sure that the insides
of the pipes are clean.
· Change flare nut to the one provided with this product.
Use a newly flared pipe.
· Avoid using thin pipes.
Do not use refrigerant other than R410A.
If other refrigerant (R22 etc.) is used, chlorine in refrige-
rant 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.
Contamination inside refrigerant piping can cause deterio-
ration of refrigerant oil etc.
INDOOR UNIT SERVICE MANUAL
Model name Service ref. Service manual No.
EHST20C-VM6HB
EHST20C-YM9HB
EHST20C-VM6B
EHST20C-YM9B
EHST20C-VM6EB
EHST20C-YM9EB
EHST20C-VM6SB
EHPT20X-VM2HB
EHPT20X-VM6HB
EHPT20X-YM9HB
EHPT20X-VM6B
EHPT20X-YM9B
EHST20C-VM6HB.UK
EHST20C-YM9HB.UK
EHST20C-VM6B.UK
EHST20C-YM9B.UK
EHST20C-VM6EB.UK
EHST20C-YM9EB.UK
EHST20C-VM6SB.UK
EHPT20X-VM2HB.UK
EHPT20X-VM6HB.UK
EHPT20X-YM9HB.UK
EHPT20X-VM6B.UK
EHPT20X-YM9B.UK
OCH531
EHSC-VM6B
EHSC-YM9B
EHSC-VM6EB
EHSC-YM9EB
EHPX-VM2B
EHPX-VM6B
EHPX-YM9B
ERSC-VM2B
EHSC-VM6B.UK
EHSC-YM9B.UK
EHSC-VM6EB.UK
EHSC-YM9EB.UK
EHPX-VM2B.UK
EHPX-VM6B.UK
EHPX-YM9B.UK
ERSC-VM2B.UK
OCH532
OCH525

3
[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.
(4) When performing service, install a filter drier simultaneously.
Be sure to use a filter drier for new 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.)
Gravimeter
Unit
Store the piping indoors, and both ends of the
piping sealed until just before brazing.
(Leave elbow joints, etc. in their packaging.)
The refrigerant oil applied to flare and flange
connections must be ester oil, ether oil or
alkylbenzene oil in a small amount.
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.
Handle tools with care.
If dirt, dust or moisture enters into refrigerant cycle, that can
cause deterioration of refrigerant oil or malfunction of com-
pressor.
Do not use a charging cylinder.
If a charging cylinder is used, the composition of refrigera-
nt will change and the efficiency will be lowered.
If dirt, dust or moisture enters into refrigerant cycle, that can
cause deterioration of refrigerant oil or malfunction of com-
pressor.
If large amount of mineral oil enters, that can cause deterio-
ration of refrigerant oil etc.
Ventilate the room if refrigerant leaks during
operation. If refrigerant comes into contact with
a flame, poisonous gases will be released.
Use the specified refrigerant only.
Never use any refrigerant other than that specified.
Doing so may cause a burst, an explosion, or fire when the
unit is being used, serviced, or disposed of.
Correct refrigerant is specified in the manuals and on the
spec labels provided with our products.
We will not be held responsible for mechanical failure,
system malfunction, unit breakdown or accidents caused
by failure to follow the instructions.
Use the following tools specifically designed for
use with R410A refrigerant.
The following tools are necessary to use R410A refrigerant.
Flare tool
Electronic refrigerant
charging scale
Vacuum pump adaptor
Size adjustment gauge
Gauge manifold
Torque wrench
Gas leak detector
Charge hose
Tools for R410A
OCH525

4
2-3. PRECAUTIONS WHEN REUSING EXISTING R22 REFRIGERANT PIPES
(1) Flowchart
[3] Service tools
Use the below service tools as exclusive tools for R410A refrigerant.
No. Tool name Specifications
1Gauge manifold · Only for R410A
· Use the existing fitting specifications. (UNF1/2)
· Use high-tension side pressure of 5.3MPa·G or over.
2Charge hose · Only for R410A
· Use pressure performance of 5.09MPa·G or over.
3Electronic scale
4Gas leak detector · Use the detector for R134a, R407C or R410A.
5Adaptor for reverse flow check · Attach on vacuum pump.
6Refrigerant charge base
7Refrigerant cylinder · Only for R410A · Top of cylinder (Pink)
· Cylinder with syphon
8Refrigerant recovery equipment
Although "-BS" model has been designed to be resistant to salt damage, observe the following precautions to maintain the
performance of the unit.
1. Avoid installing the unit in a location where it will be exposed directly to seawater or sea breeze.
2. If the cover panel may become covered with salt, be sure to install the unit in a location where the salt will be washed away by
rainwater. (If a sunshade is installed, rainwater may not clean the panel.)
3. To ensure that water does not collect in the base of the outdoor unit, make sure that the base is level, not at angle. Water
collecting in the base of the outdoor unit could cause rust.
4. If the unit is installed in a coastal area, clean the unit with water regularly to remove any salt build-up.
5. If the unit is damaged during installation or maintenance, be sure to repair it.
6. Be sure to check the condition of the unit regularly.
7. Be sure to install the unit in a location with good drainage.
2-4. PRECAUTIONS FOR SALT PROOF TYPE "-BS" MODEL
Perform the airtight test, vacuum air purging,
additional refrigerant charging (if necessary),
and gas leak check.
• Refer to the flowchart below to determine if the existing pipes can be used and if it is necessary to use a filter dryer.
• If the diameter of the existing pipes is different from the specified diameter, refer to technological data materials to confirm if
the pipes can be used.
▼
▼
▼
▼
▼
▼▼
Measure the existing pipe thickness and
check for damage.
The existing pipe thickness meets specifica-
tions and the pipes are not damaged.
Check if the existing air conditioner can operate.
After operating the cooling system for about 30
minutes, do a pump down work.
Disconnect the existing air conditioner from the
pipes.
Attach the new air conditioner
Test run The existing pipes cannot be reused.
Use new pipes.
* If the existing air conditioner cannot operate, use
a refrigerant recovery device to collect the refrigerant.
* Use new pipes for SW40-50 models.
The existing pipe thickness does not meet
specifications or the pipes are damaged.
OCH525

5
(2) Cautions for refrigerant piping work
New refrigerant R410A is adopted for replacement inverter series. Although the refrigerant piping work for R410A is same
as for R22, exclusive tools are necessary so as not to mix with different kind of refrigerant. Furthermore as the working
pressure of R410A is 1.6 times higher than that of R22, their sizes of flared sections and flare nuts are different.
1Thickness of pipes
Because the working pressure of R410A is higher compared to R22, be sure to use refrigerant piping with thickness
shown below. (Never use pipes of 0.7 mm or below.)
2Dimensions of flare cutting and flare nut
The component molecules in HFC refrigerant are smaller compared to conventional refrigerants. In addition to that,
R410A is a refrigerant, which has higher risk of leakage because its working pressure is higher than that of other refriger-
ants. Therefore, to enhance airtightness and intensity, flare cutting dimension of copper pipe for R410A has been speci-
fied separately from the dimensions for other refrigerants as shown below. The dimension B of flare nut for R410A also
has partly been changed to increase intensity as shown below. Set copper pipe correctly referring to copper pipe flaring
dimensions for R410A below. For 1/2 and 5/8 inch, the dimension B changes.
Use torque wrench corresponding to each dimension.
3Tools for R410A (The following table shows whether conventional tools can be used or not.)
1/4
3/8
1/2
5/8
3/4
6.35
9.52
12.70
15.88
19.05
0.8
0.8
0.8
1.0
—
0.8
0.8
0.8
1.0
1.0
Nominal
dimensions(inch)
Diagram below: Piping diameter and thickness
Outside
diameter (mm)
Thickness (mm)
R410A R22
1/4
3/8
1/2
5/8
3/4
6.35
9.52
12.70
15.88
19.05
9.1
13.2
16.6
19.7
—
9.0
13.0
16.2
19.4
23.3
Nominal
dimensions(inch)
Flare cutting dimensions
Outside
diameter Dimension A ( )
+0
-0.4
(mm)
R410A R22 1/4
3/8
1/2
5/8
3/4
6.35
9.52
12.70
15.88
19.05
17.0
22.0
26.0
29.0
—
17.0
22.0
24.0
27.0
36.0
Nominal
dimensions(inch)
Flare nut dimensions Outside
diameter Dimension B (mm)
R410A R22
Gauge manifold
Charge hose
Gas leak detector
Refrigerant recovery equipment
Refrigerant cylinder
Applied oil
Safety charger
Charge valve
Vacuum pump
Flare tool
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
Apply to flared section
Prevent compressor malfunction
when charging refrigerant by
spraying liquid refrigerant
Prevent gas from blowing out
when detaching charge hose
Vacuum drying and air
purge
Flaring work of piping
Bend the pipes
Cut the pipes
Weld the pipes
Refrigerant charge
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
Ester oil and alkylbenzene
oil (minimum amount)
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 by adjusting
flaring dimension
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)
(Usable by adjusting
flaring dimension)
Can R407C tools be used?
Ester oil:
Alkylbenzene oil: minimum amount
(Usable if equipped
with adopter for rever-
se flow)
(Usable by adjusting
flaring dimension)
: 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.
Dimension A
Dimension B
OCH525

6
3 FEATURES
CHARGELESS SYSTEM
PRE-CHARGED REFRIGERANT IS SUPPLIED FOR PIPING LENGTH AT SHIPMENT
Max. 10m (PUHZ-SW40/SW50)
The refrigerant circuit with LEV (Linear Expansion Valve) and power receiver always control the optimal refrigerant level
regardless of the length (10 m max. and 5 m min.) of piping. The additional refrigerant charging work during installation
often causes problems. It is completely eliminated by chargeless system. This unique system improves the quality and reli-
ability of the work done. It also helps to speed up the installation time.
PUHZ-SW40VHA PUHZ-SW50VHA
<Reference data> Plate heat exchanger (ACH50-50 plates) *2pcs [connected in parallel]
Note: "COP" and "Power input" in the above table are values that does NOT contains the "pump input (based on EN 14511)".
4 SPECIFICATIONS
PUHZ-SW40VHA
PUHZ-SW40VHA-BS
PUHZ-SW50VHA
PUHZ-SW50VHA-BS
Nominal water flow L/min 11.80
Heating
(A7/W35) Capacity kW 4.10
COP 4.80
Power input kW 0.85
Heating
(A7/W45) Capacity kW 4.10
COP 3.63
Power input kW 1.13
Heating
(A2/W35) Capacity kW 4.00
COP 3.24
Power input kW 1.24
Heating
(A2/W45) Capacity kW 4.00
COP 2.68
Power input kW 1.49
Nominal water flow L/min 10.30
Cooling
(A35/W7) Capacity kW 3.60
EER 2.71
Power input kW 1.33
Cooling
(A35/W18) Capacity kW 3.60
EER 4.65
Power input kW 0.77
(SW40)
Nominal water flow L/min 17.2
Heating
(A7/W35) Capacity kW 6.00
COP 4.42
Power input kW 1.36
Heating
(A7/W45) Capacity kW 6.00
COP 3.32
Power input kW 1.81
Heating
(A2/W35) Capacity kW 5.00
COP 2.97
Power input kW 1.68
Heating
(A2/W45) Capacity kW 5.00
COP 2.47
Power input kW 2.03
Nominal water flow L/min 12.9
Cooling
(A35/W7) Capacity kW 4.50
EER 2.38
Power input kW 1.90
Cooling
(A35/W18) Capacity kW 5.00
EER 3.96
Power input kW 1.26
(SW50)
OCH525

7
A
kW
W
kW
*
/min(CFM )
dB
dB
mm(in.)
mm(in.)
mm(in.)
kg(lbs)
kg(lbs)
L
mm(in.)
mm(in.)
Power supply (phase, cycle, voltage)
Max. current
External finish
Refrigerant control
Compressor
Model
Motor output
Starter type
Protection devices
Crankcase heater
Heat exchanger
Fan Fan(drive) %No.
Fan motor output
Airflow
Defrost method
Noise level
Dimensions
Weight
Refrigerant
Charge
Oil (Model)
Pipe size O.D.
Connection method
Between the indoor &
outdoor unit
Cooling
Heating
W
D
H
Liquid
Gas
Indoor side
Outdoor side
Height difference
Piping length
Service Ref. PUHZ-SW40VHA PUHZ-SW50VHA
PUHZ-SW40VHA-BS PUHZ-SW50VHA-BS
Munsell 3Y 7.8/1.1
Linear Expansion Valve
Hermetic
SNB130FGCM2
0.9
Inverter
—
Plate fin coil
Propeller fan %1
0.040
35(1,240)
Reverse cycle
800(31-1/2)
300+23(11-13/16+7/8)
600(23-5/8)
42(93)
R410A
2.1(4.6)
0.50(FV50S)
6.35(1/4)
12.7(1/2)
Flared
Flared
Max. 10m
Max. 40m
HP switch
Comp.surface thermo
Discharge thermo
Over current detection
Single, 50Hz, 230V
13
45
45 46 46
OUTDOOR UNIT
REFRIGERANT PIPING
Rating conditions
Nominal operating condition
Heating (A7/W35)
Outside air temperature (Dry-bulb) + 7 °C
Outside air temperature (Wet-bulb) + 6 °C
Water temperature (inlet/outlet) + 30 °C/+ 35 °C
Heating (A7/W45)
Outside air temperature (Dry-bulb) + 7 °C
Outside air temperature (Wet-bulb) + 6 °C
Water temperature (inlet/outlet) + 40 °C/+ 45 °C
Heating (A2/W35)
Outside air temperature (Dry-bulb) + 2 °C
Outside air temperature (Wet-bulb) + 1 °C
Water temperature (inlet/outlet) + 30 °C/+ 35 °C
Heating (A2/W45)
Outside air temperature (Dry-bulb) + 2 °C
Outside air temperature (Wet-bulb) + 1 °C
Water temperature (inlet/outlet) + 40 °C/+ 45 °C
Cooling (A35/W7)
Outside air temperature (Dry-bulb) + 35 °C
Outside air temperature (Wet-bulb) + 24 °C
Water temperature (inlet/outlet) + 12 °C/+ 7 °C
Cooling (A35/W18)
Outside air temperature (Dry-bulb) + 35 °C
Outside air temperature (Wet-bulb) + 24 °C
Water temperature (inlet/outlet) + 23 °C/+ 18 °C
OCH525

8
5DATA
5-1. REFILLING REFRIGERANT CHARGE (R410A : kg)
U-V
U-W
W-V
Service Ref.
Compressor model
Winding
Resistance
()
(at 20°C)
SNB130FGCM2
0.64
0.64
0.64
PUHZ-SW40VHA(-BS)
PUHZ-SW50VHA(-BS)
Additional charge is required for pipes
longer than 10 m.
Service Ref. Piping length (one way) Initial
charged
10m 20m 30m 40m 50m 60m 75m
PUHZ-SW40VHA
PUHZ-SW40VHA-BS 2.1 2.3 2.5 2.7 2.9 — — 2.5
PUHZ-SW50VHA
PUHZ-SW50VHA-BS 2.1 2.3 2.5 2.7 2.9 — — 2.5
5-2. COMPRESSOR TECHNICAL DATA
5-3. NOISE CRITERION CURVES
1.5m
1m
MICROPHONE
UNIT
GROUND
APPROXIMATE
THRESHOLD OF
HEARING FOR
CONTINUOUS
NOISE
NC-60
NC-50
NC-40
NC-30
NC-20
NC-70
PUHZ-SW40VHA(-BS)
COOLING
MODE
HEATING
45
SPL(dB)
45
LINE
90
80
70
60
50
40
30
20
10 63 125 250 500 1000 2000 4000 8000
OCTAVE BAND SOUND PRESSURE LEVEL, dB (0 dB = 0.0002 μbar)
BAND CENTER FREQUENCIES, Hz
APPROXIMATE
THRESHOLD OF
HEARING FOR
CONTINUOUS
NOISE
NC-60
NC-50
NC-40
NC-30
NC-20
NC-70
PUHZ-SW50VHA(-BS)
COOLING
MODE
HEATING
46
SPL(dB)
46
LINE
90
80
70
60
50
40
30
20
10 63 125 250 500 1000 2000 4000 8000
OCTAVE BAND SOUND PRESSURE LEVEL, dB (0 dB = 0.0002 μbar)
BAND CENTER FREQUENCIES, Hz
OCH525

9
6OUTLINES AND DIMENSIONS
PUHZ-SW40VHA PUHZ-SW40VHA-BS
PUHZ-SW50VHA PUHZ-SW50VHA-BS Unit : mm
100 mm or more as long as
no obstacle is placed on the
rear and right-and-left sides
of the unit.
*1ޓIn the place where short cycle tends to occur,cooling and heating
ޓcapacity and power consumption might get lowered 10%. Air outlet
ޓguide (optional PAC-SG58SG) will help them improve.
*2 If air discharges to the wall, the surface might det stained.
Please secure the unit firmly
with 4 foundation (M10) bolts.
(Bolts, washers and nut must
be purchased locally).
FOUNDATION BOLTS
Minimum installation space for outdoor unit
Free space around the outdoor unit
(basic example)
Piping and wiring connection can
be made from the rear direction only.
PIPING-WIRING DIRECTION
Handle for moving
Handle for
moving
18
69
10
600
300
287.5
800
Terminal connections
Left࡮࡮࡮Power supply wiring
Right࡮࡮࡮Indoor/Outdoor wiring
Service panel
Earth terminal
Service panel
for charge plug
Connection for
liquid pipe FLARE :6.35(1/4F)
Connection for
gas pipe FLARE :12.7(1/2F)
Service port 183
440
23
90
155
35°
43°
6-:33 drain hole
2-:12 drain hole
70
45
400 500
347.4
226
0
43.6
155
152
74.3
0
60 118 0
284.3
Less than
<Foundation bolt height>
18mm
100mm or more
500mm or more
2 sides should be open in
the right,left and rear side.
*1
*2
*1
350mm or more
100mm or more
Basically open
Air discharge
4-10×21 oval hole
Side air intake
Rear air intake
32.5
40
330
300
365
150 500
Installation bolt pitch
FOUNDATION
OCH525

10
7WIRING DIAGRAM
SYMBOL NAME SYMBOL NAME SYMBOL NAME
TB1
MC
MF1
21S4
63H
63HS
TH3
TH4
TH6
TH7
TH8
TH34
LEV-A, LEV-B
ACL
CY1, CY2
Terminal Block <Power Supply, Indoor/Outdoor>
Motor for Compressor
Fan Motor
Solenoid Valve (Four-Way Valve)
High Pressure Switch
High Pressure Sensor
Thermistor <Liquid>
Thermistor <Discharge>
Thermistor <2-Phase Pipe>
Thermistor <Ambient>
Thermistor <Heat Sink>
Thermistor <Comp. Surface>
Linear Expansion Valve
Reactor
Capacitor
P. B.
N. F.
C. B.
Power Circuit Board
Connection Terminal <L/N-Phase>
Connection Terminal <U/V/W-Phase>
Power Module
Converter
Main Smoothing Capacitor
Noise Filter Circuit Board
Connection Terminal <L-Phase>
Connection Terminal <N-Phase>
Connection Terminal <Ground>
52C Relay
Controller Circuit Board
Switch <Manual Defrost, Defect History,
Record Reset, Refrigerant Address>
Switch <Test Operation>
R, S
U, V, W
IPM
PFC
CB1, CB2, CB3
LI, LO
NI, NO
EI, E2, E3
52C
SW1
SW4
SW5
SW6
SW7
SW8
SW9
SWP
CN31
CNDM
CN51
SV1/CH
SS
CNM
LED1, LED2
F1, F2, F3, F4
X51, X52, X54
Switch <Function Switch, Model Select>
Switch <Model Select>
Switch <Function Switch>
Switch <Function Switch>
Switch <Function Switch>
Switch <Pump Down>
Connector <Emergency Operation>
Connector <Connection for Option>
Connector <Connection for Option>
Connector <Connection for Option>
Connector <Connection for Option>
Connector <Connection for Option>
LED<Operation Inspection Indicators>
Fuse <T6.3AL250V>
Relay
C. B.
P. B.
TH8
TH6TH7 TH4TH3
U
CB3
N. F.
21S4
LN S1S2S3
INDOOR
UNIT
POWER SUPPLY
~/N 230V 50Hz
TB1
V
W
5
2
2
2
2
RED
WHT
BLK
t° t° t° t° t°
t°
MC
CN5
(RED)
CNAC2
(RED)
CNAC1
(WHT)
LO NO
LI NI EI
CN52C
(BLK)
3
1
1
3
2
1
1
2
52C
CN2
(WHT)
CN3
(WHT)
CN5
(RED)
CN4
(WHT)
1
7
1
2
1
2
2
1
LEV-A
CNS
(WHT)
CNAC
(WHT)
CNDC
(PNK)
F2
F1
F3
F4 21S4
(GRN)
CN2
(WHT)
CN4
(WHT)
CN3S
(WHT)
TH7/6
(RED) TH3
(WHT) TH4 (WHT)
TRANS
CNVMNT
(WHT) CNMNT
(WHT)
CNM
(WHT)
LED1
LED2
X52
SV1
/CH
(GRY)
X54
63H
(YLW) CN52C
(RED)
2
5
2
141221
13
311 5
1
14
1
3
12 12
17
3
1
13
12
34 31 31
LEV-A
(WHT)
51
MS
3~
CB2CB1
R
S
U
V
W
PFC
IPM
ACL
E3E2
RED
BLU
RE D
WHT
RE D
WHT
YLW
ORN
BLK
BLK
BLK
BRN
RE D
WHT
RE D
WHT
CY1
CY2
GRN/YLW
SS
(WHT)
X51
31
MS
3~
MF1 CNF1
(WHT)
17
63H
31
TH34
21
TH34
(RED)
63HS
(WHT)
63HS
LEV-B
(RED)
M
LEV-B
51
M
CNDM
(WHT)
CN51
(WHT)
1
3
1
5
+++
SW7
SW6SW1
SW9
CN31
SW5SW8SW4SWP
12345678
12345678
OFF
ON
40V
MODEL SW6 SW5-6 *2
OFF
ON
OFF
ON
50V
OFF
ON
123456
123456
*1 MODEL SELECT
The black square ( ) indicates a switch position.
*2 SW5 -1 to 5 : Function Switch
*1 *1
PUHZ-SW40VHA PUHZ-SW40VHA-BS
PUHZ-SW50VHA PUHZ-SW50VHA-BS
OCH525

11
8WIRING SPECIFICATIONS
8-1. FIELD ELECTRICAL WIRING (power wiring specifications)
Notes: 1. Wiring size must comply with the applicable local and national code..
2. Power supply cables and Indoor/Outdoor unit connecting cables shall not be lighter than polychloroprene sheathed flexible cable.
3. Install an earth longer than other cables.
Warning:
In case of A-control wiring, there is high voltage potential on the S3 terminal caused by electrical circuit design that has no electrical insulation between
power line and communication signal line. Therefore, please turn off the main power supply when servicing. And do not touch the S1, S2, S3 terminals
when the power is energized. If isolator should be used between indoor unit and outdoor unit, please use 3-pole type.
(Design 60245 IEC 57)
S1
S2
S3
S1
S2
S3
A-Control
Outdoor Unit
3 poles isolator
Power supply
Isolator
A-Control
Indoor Unit
Outdoor unit model SW40, 50V
Outdoor unit power supply ~/N (single),
50 Hz, 230 V
Outdoor unit input capacity Main switch (Breaker) *1 16 A
Wiring
Wire No. ×
size (mm2)
Outdoor unit power supply 3 × Min. 1.5
Indoor unit-Outdoor unit *2 3 × 1.5 (Polar)
Indoor unit-Outdoor unit earth *2 1 × Min. 1.5
Remote controller-Indoor unit *3 2 × 0.3 (Non-polar)
Circuit rating
Outdoor unit L-N (single)
Outdoor unit L1-N, L2-N, L3-N (3 phase)
*4 AC 230 V
Indoor unit-Outdoor unit S1-S2 *4 AC 230 V
Indoor unit-Outdoor unit S2-S3 *4 DC 24 V
Remote controller-Indoor unit *4 DC 12 V
*1. A breaker with at least 3.0 mm contact separation in each poles shall be provided. Use earth leakage breaker (NV).
Make sure that the current leakage breaker is one compatible with higher harmonics.
Always use a current leakage breaker that is compatible with higher harmonics as this unit is equipped with an inverter.
The use of inadequate breaker can cause the incorrect operation of inverter.
*2. Max. 45 m
If 2.5 mm² used, Max. 50 m
If 2.5 mm² used and S3 separated, Max. 80 m
*3. The 10 m wire is attached in the remote controller accessory.
*4. The figures are NOT always against the ground.
S3 terminal has DC 24 V against S2 terminal. However between S3 and S1, these terminals are NOT electrically insulated by the transformer or other device.
Caution: Be sure to install N-Line. Without N-Line, it could cause damage to the unit.
OCH525

12
9REFRIGERANT SYSTEM DIAGRAM
PUHZ-SW40VHA PUHZ-SW40VHA-BS
PUHZ-SW50VHA PUHZ-SW50VHA-BS Unit : mm (inch)
Refrigerant flow in cooling
Refrigerant flow in heating
Thermistor TH7
(Ambient)
Heat exchanger
Refrigerant GAS pipe
connection ø12.7(1/2F)
Refrigerant LIQUID pipe
connection ø6.35(1/4F)
Stop valve
Strainer
#100
Power
receiver
Linear
expansion valve B
Thermistor TH6
(2-phase pipe)
Thermistor TH3
(Liquid)
Charge plug
High pressure
switch 63H
Thermistor TH4
(Discharge)
Thermistor TH34
(Comp. surface)
Compressor
Strainer
#50
Solenoid valve
(Four-way valve)
Distributor
Linear expansion valve A Strainer
#100
Stop valve
(with service port)
High pressure sensor
(63HS)
COMP
H/P SW
REV/V
Charge plug
P-Sensor
LEV-A
LEV-B
TH3
TH4
TH6
TH7
TH34
DC inverter twin rotary compressor (Mitsubishi Electric Corporation)
For protection (OFF:4.15MPa)
Change the refrigerant circuit (Heating / Cooling) and for Defrosting
High pressure / Low pressure / For production test use
For calculation of the condensing temperature from high pressure
Heating:Secondary LEV Cooling:Primary LEV
Heating:Primary LEV Cooling:Secondary LEV
Heating:Evaporating temperature Cooling:Sub cool liquid temperature
For LEV control and for compressor protection
Outdoor 2-phase pipe temperature
For fan control and for compressor frequency control
For compressor protection
For accumulation of refrigerant
Compressor
Highpressureswitch(63H)
Reversing (4-way) valve (21S4)
Charge plug
High pressure sensor (63HS)
Linear expansion valve -A
Linear expansion valve -B
Liquid temperature thermistor
Discharge temperature thermistor
2-phase pipe temperature thermistor
Ambient temperature thermistor
Comp.surface temperature thermistor
Power Receiver
Symbol Part name Detail
Power Receiver
OCH525

13
9-1. Refrigerant collecting (pump down)
Perform the following procedures to collect the refrigerant when moving the indoor unit or the outdoor unit.
1Supply power (circuit breaker).
* When power is supplied, make sure that “CENTRALLY CONTROLLED” is not displayed on the remote controller. If “CEN-
TRALLY CONTROLLED” is displayed, the refrigerant collecting (pump down) cannot be completed normally.
* Start-up of the indoor-outdoor communication takes about 3 minutes after the power (circuit breaker) is turned on. Start the
pump-down operation 3 to 4 minutes after the power (circuit breaker) is turned ON.
* In the case of multi-units control, before powering on, disconnect the wiring between the master indoor unit and the slave
indoor unit. For more details refer to the installation manual for the indoor unit.
2After the liquid stop valve is closed, set the SWP switch on the control board of the outdoor unit to ON. The compressor (outdoor
unit) and ventilators (indoor and outdoor units) start operating and refrigerant collecting operation begins. LED1 and LED2 on
the control board of the outdoor unit are lit.
* Only set the SWP switch (push-button type) to ON if the unit is stopped. However, even if the unit is stopped and the SWP
switch is set to ON less than 3 minutes after the compressor stops, the refrigerant collecting operation cannot be performed.
Wait until compressor has been stopped for 3 minutes and then set the SWP switch to ON again.
3Because the unit automatically stops in about 2 to 3 minutes when the refrigerant collecting operation is completed (LED1 off,
LED2 lit), be sure to quickly close the gas stop valve. If LED1 is lit and LED2 is off and the outdoor unit is stopped, refriger-
ant collection is not properly performed. Open the liquid stop valve completely, and then repeat step 2after 3 minutes have
passed.
* If the refrigerant collecting operation has been completed normally (LED1 off, LED2 lit), the unit will remain stopped until the
power supply is turned off.
4Turn off the power supply (circuit breaker).
* Note that when the extension piping is very long with large refrigerant amount, it may not be possible to perform a pump-
down operation. When performing the pump-down operation, make sure that the low pressure is lowered to near 0 MPa
(gauge).
Warning:
When pumping down the refrigerant, stop the compressor before disconnecting the refrigerant pipes. The compressor
may burst if air etc. get into it.
9-2. Start and finish of test run
• Operation from the indoor unit
Execute the test run using the installation manual for the indoor unit.
• Operation from the outdoor unit
By using the DIP switch SW4 on the control board of outdoor unit, test run can be started and finished, and its operation
mode (cooling/heating) can be set up.
1Set the operation mode (cooling/heating) using SW4-2.
2Turn on SW4-1 to start test run with the operation mode set by SW4-2.
3Turn off SW4-1 to finish the test run.
• There may be a faint knocking sound around the machine room after power is supplied, but this is
no problem with product because the linear expansion pipe is just moving to adjust opening pulse.
• There may be a knocking sound around the machine room for several seconds after compressor
starts operating, but this is no problem with product because the check valve itself, generates the
sound because pressure difference is small in the refrigerant circuit.
Note:
The operation mode cannot be changed by SW4-2 during test run. (To change test run mode, stop the unit by SW4-1,
change the operation mode and restart the test run by SW4-1.)
OFF 12
ON
<SW4>


Stop Operation
Cooling Heating
OCH525

14
10 TROUBLESHOOTING
10-1. 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 Error code Actions to be taken for service (summary)
The trouble is reoccurring.
Displayed Judge what is wrong and take a corrective action according to
“10-3. Self-diagnosis action table”.
Not displayed Conduct troubleshooting and ascertain the cause of the
trouble.
The trouble is not reoccurring.
Logged
1Consider 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.
2Reset error code logs and restart the unit after finishing
service.
3There is no abnormality in electrical component, controller
board, and etc.
Not logged
1Re-check the abnormal symptom.
2Conduct troubleshooting and ascertain the cause of the
trouble.
3Continue to operate unit for the time being if the cause is
not ascertained.
4There is no abnormality concerning of parts such as
electrical component, controller board, and etc.
10-2. CHECK POINT UNDER TEST RUN
Before test run
• After installation of outdoor unit, 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 500 V Megger
and check that it is 1.0 M or over.
• 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.)
Warning:
Do not use the system if the insulation resistance is less than 1.0 MΩ.
Caution:
Do not carry out this test on the control wiring (low voltage circuit) terminals.
OCH525

15
10-3. SELF-DIAGNOSIS ACTION TABLE
<Abnormalities detected when the power is put on> (Note 1) Refer to indoor unit section for code P and code E.
Error Code
Abnormal points and detection method
Case Judgment and action
None —
1No voltage is supplied to termi-
nal 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)
2Electric power is not supplied
to power supply terminal of out-
door power circuit board.
a) Contact failure of power
supply terminal
b) Open phase on the outdoor
power circuit board
(Disconnection of terminal
on outdoor power circuit
board)
3Electric power is not supplied
to outdoor controller circuit
board.
a) Disconnection of connector
(CNDC)
4Disconnection of reactor (ACL)
5Disconnection of outdoor noise
filter circuit board or parts fail-
ure in outdoor noise filter circuit
board
6Defective outdoor power circuit
board
7Defective outdoor controller
circuit board
1Check following items.
a) Power supply breaker
b) Connection of power supply terminal
block. (TB1)
c) Connection of power supply terminal
block. (TB1)
2Check following items.
a) Connection of power supply terminal block.
(TB1)
b) Connection of terminal on outdoor power
circuit board.
3Check connection of the connector (CNDC)
on the outdoor controller circuit board.
Check connection of the connector, LD1
and LD2 on the outdoor power circuit board.
Refer to 10-9.
4Check connection of reactor. (ACL)
Check connection of “LO” and
“NO” on the outdoor noise filter circuit board.
Check connection of “R” and “S” on the
outdoor power circuit board.
Refer to 10-9.
5a) Check connection of outdoor noise filter
circuit board.
b) Replace outdoor noise filter circuit board.
Refer to 10-9.
6Replace outdoor power circuit board.
7Replace controller board (When items
above are checked but the units can not be
repaired.)
F5
63H connector open
Abnormal if 63H connector circuit is open
for 3 minutes continuously after power sup-
ply.
63H: High-pressure switch
1Disconnection or contact failure
of 63H connector on outdoor
controller circuit board
2Disconnection or contact failure
of 63H
363H is working due to defective
parts.
4Defective outdoor controller
circuit board
1Check connection of 63H connector on
outdoor controller circuit board.
Refer to 10-9.
2Check the 63H side of connecting wire.
3Check continuity by tester.
Replace the parts if the parts are defective.
4Replace outdoor controller circuit board.
OCH525

16
Error Code
Abnormal points and detection method Judgment and action
Eb
Miswiring of indoor/outdoor unit
connecting wire (converse wiring or
disconnection)
Outdoor controller circuit board can
automatically set the unit number of indoor
units.
Abnormal if the indoor unit number can
not be set within 4 minutes after power
on because of Miswiring (converse wiring
or disconnection) of indoor/outdoor unit
connecting wire.
EC
Start-up time over
The unit cannot finish start-up process
within 4 minutes after power on.
Case
1Contact failure of indoor/
outdoor unit connecting wire
2Diameter or length of indoor/
outdoor unit connecting wire is
out of specified capacity.
72 or more outdoor units have
refrigerant address “0” .
(In case of group control)
8Noise has entered into power
supply or indoor/outdoor unit
connecting wire.
1Contact failure or miswiring of
indoor/outdoor unit connecting
wire
2Diameter or length of indoor/
outdoor unit connecting wire is
out of specified capacity.
4Defective transmitting receiving
circuit of outdoor controller circuit
board
5Defective transmitting receiving
circuit of indoor controller board
6Defective indoor power board
72 or more outdoor units have
refrigerant address “0” .
(In case of group control)
8Noise has entered into power
supply or indoor/outdoor unit
connecting wire.
Miswiring of indoor/outdoor unit
connecting wire
1. Outdoor controller circuit board can
automatically check the number of
connected indoor units. Abnormal if the
number cannot be checked automatically
due to miswiring of indoor/outdoor unit
connecting wire and etc. after power is
turned on for 4 minutes.
2. Abnormal if outdoor controller circuit
board recognizes excessive number of
indoor units.
1Check disconnection or looseness or polarity
of indoor/outdoor unit connecting wire of
indoor and outdoor units.
2Check diameter and length of indoor/outdoor
unit connecting wire.
Total wiring length: 80 m
(including wiring connecting each indoor unit
and between indoor and outdoor unit)
Also check if the connection order of flat
cable is S1, S2, S3.
3Check the number of indoor units that are
connected to one outdoor unit. (If EA is
detected)
4~6Turn the power off once, and on again to
check.
Replace outdoor controller circuit board,
indoor controller board or indoor power
board if abnormality occurs again.
7Check if refrigerant addresses (SW1-3 to
SW1-6 on outdoor controller circuit board) are
overlapping in case of group control system.
8Check transmission path, and remove the
cause.
wThe descriptions above, 1-8, are for EA, Eb
and EC.
1Contact failure or miswiring of
indoor/outdoor unit connecting
wire
2Diameter or length of indoor/
outdoor unit connecting wire is
out of specified capacity.
3Excessive number of indoor
units are connected to 1
outdoor unit. (4 units or more)
4Defective transmitting receiving
circuit of outdoor controller
circuit board
5Defective transmitting receiving
circuit of indoor controller board
6Defective indoor power board
72 or more outdoor units have
refrigerant address “0” .
(In case of group control)
8Noise has entered into power
supply or indoor / outdoor unit
connecting wire.
EA
EE
Incorrect connection
The outdoor unit does not receive the sig-
nals of I/F or FTC.
1A device other than Interface
unit or Flow temp. controller
unit is connected to the unit.
1Connect I/F or FTC to the unit.
OCH525

17
Error Code
Abnormal points and detection method Judgment and action
U1
High pressure (High-pressure switch
63H operated)
Abnormal if high-pressure switch 63H
operated ( w) during compressor opera-
tion.
wSW40,50 (63H) : 4.15 MPa
63H: High-pressure switch
1Short cycle of indoor unit
2Clogged filter of indoor unit
3Decreased airflow caused by
dirt of indoor fan
4Dirt of indoor heat exchanger
5Locked indoor fan motor
6Malfunction of indoor fan motor
7Defective operation of stop
valve (Not full open)
8Clogged or broken pipe
9Locked outdoor fan motor
0Malfunction of outdoor fan
motor
1Short cycle of outdoor unit
2Dirt of outdoor heat exchanger
3Decreased airflow caused by
defective inspection of outside
temperature thermistor
(It detects lower temperature
than actual temperature.)
4Disconnection or contact failure
of connector (63H) on outdoor
controller board
5Disconnection or contact failure
of 63H connection
6Defective outdoor controller
board
7Defective action of linear
expansion valve
8Malfunction of fan driving circuit
1~6Check indoor unit and repair defect.
7Check if stop valve is fully open.
8Check piping and repair defect.
9~2Check outdoor unit and repair defect.
3Check the detected temperature of outside
temperature thermistor on LED display.
(SW2 on A-Control Service Tool : Refer to
10-10.)
4~6Turn the power off and check F5 is
displayed when the power is turned again.
When F5 is displayed, refer to “Judgment
and action” for F5.
7Check linear expansion valve.
Refer to 10-6.
8Replace outdoor controller board.
Case
U2
<Abnormalities detected while unit is operating>
High discharging temperature
(1) Abnormal if discharge temperature
thermistor (TH4) exceeds 125:or
110: continuously for 5 minutes.
Abnormal if discharge temperature
thermistor (TH4) exceeds 110:or
more continuously for 30 seconds
after 90 seconds have passed since the
defrosting operation started.
(2) Abnormal if discharge superheat
(Cooling: TH4 – T63HS /
Heating: TH4 – T63HS) exceeds 70:
continuously for 10 minutes.
High comp. surface temperature
Abnormal if comp. surface temperature
(TH34) exceeds 125:.In the case of
high comp. surface temperature error,
compressor does not restart unless the
thermistor (TH34) becomes less than
95:.
1Overheated compressor
operation caused by shortage
of refrigerant
2Defective operation of stop
valve
3Defective thermistor
4Defective outdoor controller
board
5Defective action of linear
expansion valve
6Clogging with foreign objects in
refrigerant circuit
wClogging occur in the parts
which become below freezing
point when water enters in
refrigerant circuit.
1Check intake superheat.
Check leakage of refrigerant.
Charge additional refrigerant.
2Check if stop valve is fully open.
34
Turn the power off and check if U3 is
displayed when the power is turned on again.
When U3 is displayed, refer to “Judgement
and action” for U3.
5Check linear expansion valve.
Refer to 10-6.
6After recovering refrigerant, remove water
from entire refrigerant circuit under vacuum
more than 1 hour.
U3
Open/short circuit of discharge
temperature thermistor (TH4) / comp.
surface thermistor (TH34)
Abnormal if open (3:or less) or short
(217:or more) is detected during
compressor operation.
(Detection is inoperative for 10 minutes
of compressor starting process and for 10
minutes after and during defrosting.)
1Disconnection or contact failure
of connector (TH4/TH34) on
the outdoor controller circuit
board
2Defective thermistor
3Defective outdoor controller
circuit board
1Check connection of connector (TH4/TH34)
on the outdoor controller circuit board.
Check breaking of the lead wire for
thermistor (TH4/TH34). Refer to 10-9.
2Check resistance value of thermistor (TH4/
TH34) or temperature by microcomputer.
(Thermistor/TH4/TH34: Refer to 10-6.)
(SW2 on A-Control Service Tool: Refer to 10-10.)
3Replace outdoor controller board.
OCH525

18
Error Code
Abnormal points and detection method
Case Judgment and action
U5
Temperature of heatsink
Abnormal if heatsink thermistor (TH8)
detects temperature indicated below.
SW40/50··········································· 84:
1The outdoor fan motor is
locked.
2Failure of outdoor fan motor
3Air flow path is clogged.
4Rise of ambient temperature
5Defective thermistor
6Defective input circuit of
outdoor power circuit board
7Failure of outdoor fan drive
circuit
12 Check outdoor fan.
3Check air flow path for cooling.
4Check 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, follow the
action to be taken for U4.
5Check resistance value of thermistor (TH8)
or temperature by microcomputer.
(Thermistor/TH8: Refer to 10-6.)
(SW2 on A-Control Service Tool: Refer to 10-10.)
6Replace outdoor power circuit board.
7Replace outdoor controller circuit board.
U4
Open/short of outdoor unit thermistors
(TH3, TH6, TH7, and TH8)
Abnormal if open or short is detected
during compressor operation.
Open detection of thermistors TH3 and
TH6 is inoperative 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.
(PAC-SK52ST)
(Refer to 10-10.)
1Check connection of connector (TH3,TH6/
TH7) on the outdoor controller circuit board.
Check connection of connector (CN3) on the
outdoor power circuit board.
Check breaking of the lead wire for thermistor
(TH3,TH6,TH7,TH8). Refer to 10-9.
2Check resistance value of thermistor
(TH3,TH6,TH7,TH8) or check temperature by
microcomputer.
(Thermistor/TH3,TH6,TH7,TH8: Refer to 10-6.)
(SW2 on A-Control Service Tool: Refer to
10-10.)
3Replace outdoor controller circuit board.
1Disconnection or contact failure
of connectors
Outdoor controller circuit
board: TH3, TH6/TH7
Outdoor power circuit board:
CN3
2Defective thermistor
3Defective outdoor controller
circuit board
()
U6
Power module
Check abnormality by driving power module
in case overcurrent is detected.
(UF or UP error condition)
1Outdoor stop valve is closed.
2Decrease of power supply voltage
3Looseness, disconnection or
converse of compressor wiring
connection
4Defective compressor
5Defective outdoor power circuit
board
1Open stop valve.
2Check facility of power supply.
3Correct the wiring (U•V•W phase) to
compressor. Refer to 10-9 (Outdoor power
circuit board).
4Check compressor referring to 10-6.
5Replace outdoor power circuit board.
U7
Too low superheat due to low discharge
temperature
Abnormal if discharge superheat is
continuously detected less than or equal
to -15:for 3 minutes even though linear
expansion valve has minimum open pulse
after compressor starts operating for 10
minutes.
1Disconnection or loose
connection of discharge
temperature thermistor (TH4)
2Defective holder of discharge
temperature thermistor
3Disconnection or loose connection
of linear expansion valve’s coil
4Disconnection or loose
connection of linear expansion
valve’s connector
5Defective linear expansion valve
12 Check the installation conditions of
discharge temperature thermistor (TH4).
3Check the coil of linear expansion valve.
Refer to 10-8.
4Check the connection or contact of LEV-A and
LEV-B on outdoor controller circuit board.
5Check linear expansion valve.
Refer to 10-6.
Thermistors Open detection Short detection
Symbol Name
TH3 Thermistor <Liquid> - 40 °C or below 90 °C or above
TH6 Thermistor <2-phase pipe> - 40 °C or below 90 °C or above
TH7 Thermistor <Amibient> - 40 °C or below 90 °C or above
TH8 Thermistor <Heatsink> - 27 °C or below 102 °C or above
U8
Outdoor fan motor
Abnormal if rotational frequency of the fan
motor is not detected during DC fan motor
operation.
Fan motor rotational frequency is abnormal
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.
1Failure in the operation of the
DC fan motor
2Failure in the outdoor circuit
controller board
1Check or replace the DC fan motor.
2Check the voltage of the outdoor circuit
controller board during operation.
3Replace the outdoor circuit controller board.
(when the failure is still indicated even after
performing the action 1above.)
OCH525

Error Code Abnormal point and detection method Case Judgment and action
19
U9
Detailed
codes
To find out the details about U9 error, turn ON SW2-1, 2-2, 2-3, 2-4, 2-5 and 2-6 when U9 error occurs.
To find out the detail history (latest) about U9 error, turn ON SW2-1, 2-2 and 2-6.
Refer to 10-10.
01
Overvoltage error
• Increase in DC bus voltage to
420V
1
Abnormal increase in power source volt-
age
2Disconnection of compressor wiring
3Defective outdoor power circuit
board
4
Compressor has a ground fault.
1 Check the field facility for the power supply.
2Correct the wiring (U.V.W phase) to
compressor. Refer to 10-9 (Outdoor
power circuit board).
3Replace outdoor power circuit board.
4Check compressor for electrical
insulation. Replace compressor.
02
Undervoltage error
• Instantaneous decrease in DC
bus voltage to 200V
1Decrease in power source voltage,
instantaneous stop.
2
Disconnection or loose connection
of CN52C on the outdoor noise filter
circuit board/controller circuit board
3 Defective converter drive circuit in
outdoor power circuit board
4Defective 52C drive circuit in outdoor
noise filter circuit board
1 Check the field facility for the power
supply.
2Check CN52C wiring.
3Replace outdoor power circuit board.
4Replace outdoor noise filter circuit
board.
04
Input current sensor error
• Decrease in input current
through 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.
1
Disconnection or loose connection of
CN5 on the outdoor power circuit board/
CNCT on the outdoor noise filter board
2Defective ACCT (AC current trans)
on the outdoor noise filter circuit
board
3Defective input current detection
circuit in outdoor power circuit board
4
Defective outdoor controller circuit board
1Check CN5/CNCT wiring.
2Replace outdoor noise filter circuit
board.
3Replace outdoor power circuit board.
4Replace outdoor controller circuit board.
08
Abnormal power synchronous
signal
• No input of power synchronous
signal to power circuit board
• Power synchronous signal
of 44 Hz or less, or 65 Hz or
more is detected on power
circuit board.
1Distortion of power source voltage,
Noise superimposition.
2Disconnection or loose connection
of earth wiring
3Disconnection or loose connection
of CN2 on the outdoor power circuit
board /controller circuit board
4Defective power synchronous signal
circuit in outdoor controller circuit
board
5Defective power synchronous signal
circuit in outdoor power circuit board
1Check the field facility for the power
supply.
2Check earth wiring.
3Check CN2 wiring.
4Replace outdoor controller circuit board.
5Replace outdoor power circuit board.
10
PFC error (Overvoltage/
Undervoltage/Overcurrent)
• PFC detected any of the fol-
lowings
a) Increase of DC bus voltage
to 420V.
b) Decrease in PFC control
voltage to 12V DC or lower
c) Increase in input current to
50A peak
1
Abnormal increase in power source
voltage
2Decrease in power source voltage,
instantaneous stop
3Disconnection of compressor wiring
4Misconnection of reactor (ACL)
5
Defective outdoor power circuit board
6 Defective reactor (ACL)
7 Disconnection or loose connection
of CN2 on the outdoor power circuit
board/controller circuit board
PFC/IGBT error (Undervoltage)
• When compressor is running,
DC bus voltage stays at 310V or
lower for consecutive 10 seconds
1Incorrect switch settings on the
outdoor controller circuit board for
model select
2Defective outdoor power circuit
board
3Defective outdoor controller circuit
board
1Correction of a model select
2Replace outdoor power circuit board.
3Replace outdoor controller circuit board.
12 Check the field facility for the power
supply.
3Correct the wiring (U.V.W phase) to
compressor. Refer to 10-9 (Outdoor
power circuit board).
4Correct the wiring of reactor (ACL).
5Replace outdoor power circuit board.
6Replace reactor (ACL).
7Check CN2 wiring.
20
OCH525

Error Code
Abnormal points and detection method
Case Judgment and action
20
UP
Compressor overcurrent interruption
Abnormal if overcurrent DC bus or
compressor is detected after compressor
starts operating for 30 seconds.
1Stop valve of outdoor unit is
closed.
2Decrease of power supply
voltage
3Looseness, disconnection or
converse of compressor wiring
connection
4Defective fan of indoor/outdoor
units
5Short cycle of indoor/outdoor
units
6Defective input circuit of
outdoor controller board
7Defective compressor
8Defective outdoor power circuit
board
9Dip switch setting difference of
outdoor controller circuit board
1Open stop valve.
2Check facility of power supply.
3Correct the wiring (U•V•W phase) to
compressor. Refer to 10-9 (Outdoor power
circuit board).
4Check indoor/outdoor fan.
5Solve short cycle.
6Replace outdoor controller circuit board.
WBefore 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.
7Check compressor. Refer to 10-6.
8Replace outdoor power circuit board.
9 Check the dip switch setting of outdoor
controller 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.
1Stop valve is closed.
2Decrease of power supply
voltage
3Looseness, disconnection or
converse of compressor wiring
connection
4Defective compressor
5Defective outdoor power board
6Dip switch setting difference of
outdoor controller circuit board.
1Open stop valve.
2Check facility of power supply.
3 Correct the wiring (U•V•W phase) to
compressor.
Refer to 10-9 (Outdoor power circuit board).
4Check compressor.
Refer to 10-6.
5Replace outdoor power circuit board.
6Check the dip switch setting of outdoor
controller circuit board.
Refer to "Model Select" in "1) Function of
switches" in 10-10.
Ud
Over heat protection
Abnormal if liquid thermistor (TH3) detects
70: or more during compressor opera-
tion.
1Defective outdoor fan (fan
motor) or short cycle of out-
door unit during cooling opera-
tion
2Defective liquid thermistor
(TH3)
3Defective outdoor controller
board
1Check outdoor unit air passage.
23 Turn the power off and on again to check
the error code. If U4 is displayed, follow the
U4 processing direction.
UE
Abnormal pressure of pressure sensor
(63HS)
Abnormal if pressure sensor (63HS)
detects 0.1 MPa or less.
Detection is inoperative for 3 minutes after
compressor starting and 3 minutes after
and during defrosting.
1Disconnection or contact
failure of connector (63HS) on
the outdoor controller circuit
board
2Defective pressure sensor
3Defective outdoor controller
circuit board
1Check connection of connector (63HS) on
the outdoor controller circuit board.
Check breaking of the lead wire for
thermistor (63HS).
2Check pressure by microprocessor.
(Pressure sensor/ 63HS)
(SW2: Refer to 10-10.)
3Replace outdoor controller board.
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 in case of test run mode.)
• Abnormal if 40A of input current is
detected or 37A or more of input current
is detected for 10 seconds continuously.
1Disconnection of compressor
wiring
2Defective circuit of current
sensor on outdoor power circuit
board
3Decrease of power supply
voltage
1Correct the wiring (U•V•W phase) to
compressor. Refer to 10-9 (Outdoor power
circuit board).
2Replace outdoor power circuit board.
3Check the facility of power supply.
OCH525