Mitsubishi Electric QUHZ-W40VA User manual

SERVICE MANUAL
AIR TO WATER HEAT PUMP
R744
Outdoor Unit
[Model Name]
QUHZ-W40VA
Outdoor Unit
No.GHH15010
CONTENTS
1. SAFETY PRECAUTION................................... 2
2. SPECIFICATIONS............................................ 3
3. DATA
............................................................. 4
4. OUTLINES AND DIMENSIONS..................... 6
5. WIRING DIAGRAM........................................ 7
6. REFRIGERANT SYSTEM DIAGRAM ............... 8
7. TROUBLESHOOTING ................................... 9
8. DISASSEMBLY PROCEDURE...................... 24
PARTS CATALOG (GHB15010)
Notes:
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GHH15010 2
SAFETY PRECAUTION
1
1-1. ALWAYS OBSERVE FOR SAFETY
Before obtaining access to terminal, all supply circuits must be disconnected.
Preparation before the repair service.
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Precautions during the repair service.
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GHH15010 3
SPECIFICATIONS
2
2-1. SPECIFICATIONS
1ø,230V,50HzPower supply (Phase,Voltage,Frequency)
Nominal water flow rate(Heating mode) 5.7
4kW
kW
kW
kW
kW
kW
m3/min
kW
L/min
L/min
L/min
L
CapacityHeating
$:ǻ 4.65
0.86
COP
Capacity
COP
Power input
kW
Power input
Capacity
COP
Power input
4Heating
$:ǻ 3.2
1.25
1.35
1.4Nominal water flow rate(DHW mode)
5DHW
$:ǻ 3.7
Outdoor unit specifications
Service ref. QUHZ-W40VA
4.7AHeating(A7/W35)
Heating(A7/W35)
Running current
6.8
1.3
0.050
34
1,200
ADHW(A7/W65)
DHW(A7/W65)
80
85
䠂
䠂
Power factor
12AMax.current
Galvanized plateOuter casing
Munsell 2.5Y 7/1External finish
Liner expansion valveRefrigerant control
Hermetic single rotalyCompressor
KXB045FJKModel
Motor output
Inverter
0.47 (PAG)
Start type
Protection devices HP switch
Discharge thermo
Oil(Model)
Plate fin coilAirHeat exchanger
Twisted & spiral Gas coolerWater
Propeller fan ×1Fan(drive)×No.Fan
Fan motor output
Air flow
(CFM)
dB
Hot gas
43/53
300+20 (11‐13/16+13/16)
Defrost method
Noise level(SPL/PWL) Heating(A7/W55)
809+70 (31‐7/8+2‐3/4)mm(in)
mm(in)
mm(in)
iWidthDimensions
Depth
Height
57 (125.7)
1.15 (2.54)
-15 to +35
-15 to +35
+9 to +55
+9 to +55
715 (28‐1/8)
kg(lb)
kg(lb)
Weight
R744Refrigerant
Quantity
Heating
Guaranteed operating range (Outdoor)
DHW
Heating
DHW
Heating
DHW
+7℃
+6℃
+25/+35℃
+2℃
+1℃
+25/+35℃
+7℃
+6℃
+15/+65℃
+60䉝
䉝
䉝
䉝
䉝
Outlet water temp.
（Max) +72䉝
Nominal return water temperature range
3 to 8Water flow rate range (Heating)
Nominal operating condition
+HDWLQJ$:ǻ
+HDWLQJ$:ǻ
Outside air temperature(Dry-bulb)
Outside air temperature(Wet-bulb)
Water temperature(inlet/outlet)
Outside air temperature(Dry-bulb)
Outside air temperature(Wet-bulb)
Water temperature(inlet/outlet)
'+:$:ǻ
Outside air temperature(Dry-bulb)
Outside air temperature(Wet-bulb)
Water temperature(inlet/outlet)

GHH15010 4
DATA
3
1m
MICROPHONE UNIT
GROUND
3-1. NOISE CRITERION CURVES
OCTAVE BAND SOUND PRESSURE LEVEL, dB (0 dB = 0.0002 bar)
BAND CENTER FREQUENCIES, Hz
NOTCH
HEATING
A7/W55
43
SPL(dB) LINE
NC-70
NC-60
NC-50
NC-40
NC-30
NC-20
10
20
30
40
50
60
70
80
90
63 125 250 500 1000 2000 4000 8000
APPROXIMATE
THRESHOLD OF
HEARING FOR
CONTINUOUS
NOISE
［dB］
125 250 500 1000 2000 4000 8000 OA 63
QUHZ-W40VA 4345.3 46.4 40.9 35.6 33.0 25.5 21.446.4
BAND CENTER FREQUENCIES, Hz
FORMNAME

GHH15010 5
3-2. STANDARD OPERATION DATA
Mode
TotalElectrical circuit
Refrigerant circuit
Water conditions
Outdoor conditions
Capacity
Input
Outdoor unit
Phase, Hz
Voltage
Current
Discharge pressure
Discharge temperature
Flow volume
Outlet water temperature
Intake air temperature
kW
kW
V
A
MPa
ºC
L/min
ºC
D.B. ºC
W.B. ºC
DHW
(A7/W35)
Heating
(A7/W65)
4.00 5.00
0.86 1.35
QUHZ-W40VA
1, 50Hz
230 230
4.7 6.8
7.4 9.7
70 100
5.7 1.4
35 65
77
66
The unit of pressure has been changed to MPa based on international SI system.
The conversion factor is: 1 (MPa) = 10.2 (kgf/cm2)

GHH15010 6
QUHZ-W40VA
OUTLINES AND DIMENSIONS
4
Unit: mm
Bolt pitch
for installation
303
8
406
715
21 70809
155 500
Service panel
Valve cover
Pipe connection B (G1/2)
Pipe connection A (G1/2)
207
184
172
20
127 (80)
Air out
Bolt pitch for installation
2 elongate holes (10X21)
2 notch holes of U-shaped
Air in
Air in
319~330
300
40
360

GHH15010 7
5 WIRING DIAGRAM
QUHZ-W40VA

GHH15010 8
REFRIGERANT SYSTEM DIAGRAM6
Symbol
MC
HPS
MUFF
GC
SLHX
ST
LEV
CT
EVA
TH1
TH2
TH3
TH4
MF
FAN
Part name
Compressor
High pressure switch
Muffler
Gascooler
Suction line heat exchanger
Strainer
Linear expansion valve
Capillary tube
Evaporator
Discharge temperature thermistor
Defrost thermistor
Ambient temperature thermistor
Hot water temperature thermistor
Fan motor
Propeller Fan
Detail
DC inverter single rotary compressor(Mitsubishi Electric Corporation)
For protection(OFF:15MPa)
For noise reduction
Heat exchanger (2pass)
#100
For LEV Control and compressor protection
For defrost control
For fan control and for compressor frequency control
For DHW pump control
FAN
TH2
MF
EVA
TH3 CT
LEV
ST
SLHX
MC
TH1 MUFF
HPS
TH4
Water OUT
Water IN
GC

GHH15010 9
TROUBLESHOOTING7
7-1. TROUBLESHOOTING
7-2. CHECK POINT UNDER TEST RUN
Unit conditions
at service Check code Actions to be taken for service (summary)
The trouble is
reoccurring. Displayed
Not displayed
The trouble is not
reoccurring. Logged
Not logged
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control screen of the cylinder unit.
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is operating.
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the corresponding actions to be taken for service (summary).
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polarities) and defective contacts.
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outdoor control board.
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Lit -> Normal display
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perform the required action.
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perform the required action.
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perform the required action.
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symptoms again. Check the installation environ-
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the problem occurred.
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and perform the required action.
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(4) No abnormality in electric parts and control
ERDUGVHWF
(1) Check for abnormal symptoms again.
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the problem.
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(4) No abnormality in electric parts and control
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GHH15010 10
7-3. SELF-DIAGNOSIS ACTION TABLE
Abnormal point and
detection method
CaseCheck Code
Check LED
LED2
RED
Out
Outdoor unit emergency stop
Out
3
times Lit
2
times Out
4
times Out
6
times Out
LED1
GREEN
Judgment and action
E6
or
None
*< Caution >
Pay attention to electric shock
since the condensers
[C61/C62/C63/C65] are
sometimes high voltage (300 V
or more).
*The LEDs (red, green) light
when the condenser is normal.
(1) Power is not being supplied to
the outdoor unit
a) Earth leakage circuit breaker
of the cylinder unit is turned off
b) Defective power line not
connected or terminal contact
c) Power transmission line not
connected or defective terminal
contact
(2) Power is not being supplied to
the outdoor inverter p.c. board
a) Loose terminal block (TB)
power terminal [S1/S2/S3]
b) Loose reactor (L61) terminal
c) Loose relay (X64) terminal
(3) Defective outdoor inverter p.c.
board
(1) Check the following items
a) Earth leakage circuit breaker
b) Power line connections
c) Power transmission line
connections
(2) Check the following items
a) Terminal block (TB) power
terminal [S1/S2/S3] connections
b) Reactor (L61) connections
c) Relay (X64) connections
(3) Replace the outdoor inverter
p.c. board
(1) Environment is outside the
possible operating temperature
of the outdoor unit
(2) Defective THERMO_ASSY
AMB (TH3)
Ɣ'HWHFWLRQPHWKRG
THERMO_ASSY AMB (TH3)
detects 50°C or higher
Excessive ambient temperature (1) Improve the installation
environment
(2) Replace the THERMO_ASSY
AMB (TH3)
(1) Defective board temperature
thermistor on outdoor inverter
p.c. board
(2) Defective microcomputer on
outdoor inverter p.c. board
Ɣ'HWHFWLRQPHWKRG'LVFRQQHFWLRQ
or short circuit detected
Ɣ'LVFRQQHFWLRQ'LVFRQQHFWLRQ
continued for 1 second from 1
minute onwards after start of
compressor operation
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continued for 1 second at all
times
Ɣ&RQQHFWRU1RQH%RDUG
mounting
Disconnection of Outdoor inverter
p.c. board temp. thermistor
(1)(2) Replace outdoor inverter
p.c. board
(1) Defective outdoor inverter p.c.
board
Primary current abnormality
Ɣ'HWHFWLRQPHWKRG'HIHFWLYH
primary current sensor detected
for 1 second
(1) Replace the outdoor inverter
p.c. board
(1) Defective outdoor inverter p.c.
board
(2) Overcurrent due to LEV
malfunction
a) Loose LEV coil
b) Loose connector [CN724]
c) LEV coil disconnection
d) LEV unit malfunction
(3) Compressor malfunction
(locked，out-of-phase, phase
interruption)
(4) Power waveform distortion,
noise
Overcurrent abnormality
Ɣ'HWHFWLRQPHWKRG2YHUFXUUHQW
detected by secondary current
(1) Replace outdoor inverter p.c.
board
(2) Check the LEV coil.
(See "9-4. HOW TO CHECK THE
PARTS.")
a) Install the LEV coil
b) Connect the connector
c) Replace the LEV coil
d) Replace the outdoor unit
(3) Replace the outdoor unit
(4) Check to see if the power
waveform is normal

GHH15010 11
Abnormal point and
detection method
CaseCheck Code
Check LED
LED2
RED
8
times
8
times
9
times
9
times
10
times
10
times
Lit 6
times
Lit 7
times
LED1
GREEN
Judgment and action
E6
or
None
(1) Defective connector (CN641)
connection
(2) Defective (TH1)
a) Thermistor (TH1) disconnec-
tion
b) Thermistor (TH1) short circuit
(3) Defective outdoor inverter
p.c. board
Ɣ'HWHFWLRQPHWKRG'LVFRQQHF-
tion or short circuit detected
Ɣ'LVFRQQHFWLRQ°C or less
continued for 1 second 10
minutes onwards after start of
compressor operation
Ɣ6KRUWFLUFXLW°C or less
continued for 1 second at all
times
Ɣ&RQQHFWRU&1
6KRUWFLUFXLWRUGLVFRQQHFWLRQRI
discharge temp. thermistor(TH1) (1) Connect connector (CN641)
(2) Check the resistance value
and temperature of the
thermistor (TH1).
6HH+2:72&+(&.7+(
3$576
a) Replace thermistor (TH1)
b) Replace thermistor (TH1)
(3) Replace the outdoor inverter
p.c. board
(1) Defective connector (CN641)
connection
(2) Defective (TH2)
a) Thermistor (TH2) disconnec-
tion
b) Thermistor (TH2) short circuit
(3) Defective outdoor inverter
p.c. board
6KRUWFLUFXLWRUGLVFRQQHFWLRQRI
defrost temp. thermistor(TH2）
Ɣ'HWHFWLRQPHWKRG'LVFRQQHF-
tion or short circuit detected
Ɣ'LVFRQQHFWLRQ°C or less
continued for 1 second at start
of compressor operation
Ɣ6KRUWFLUFXLW°C or more
continued for 1 second at all
times
Ɣ&RQQHFWRU&1
(1) Connect connector (CN641)
(2) Check the resistance value
and temperature of the
thermistor (TH2).
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3$576
a) Replace thermistor (TH2)
b) Replace thermistor (TH2)
(3) Replace the outdoor inverter
p.c. board
(1) Defective connector (CN643)
connection
(2) Defective (TH3)
a) Thermistor (TH3) disconnec-
tion
b) Thermistor (TH3) short circuit
(3) Defective outdoor inverter
p.c. board
6KRUWFLUFXLWRUGLVFRQQHFWLRQRI
ambient temp. thermistor(TH3)
Ɣ'HWHFWLRQPHWKRG'LVFRQQHF-
tion or short circuit detected
Ɣ'LVFRQQHFWLRQ°C or less
detected for 1 second at start of
compressor operation
Ɣ6KRUWFLUFXLW°C or less
continued for 1 second at all
times
Ɣ&RQQHFWRU&1
(1) Connect connector (CN643)
(2) Check the resistance value
and temperature of the
thermistor (TH3).
6HH+2:72&+(&.7+(
3$576
a) Replace thermistor (TH3)
b) Replace thermistor (TH3)
(3) Replace the outdoor inverter
p.c. board
(1) Defective outdoor inverter
p.c. board
Abnormality of DC voltage
Ɣ'HWHFWLRQPHWKRG'HWHFWLRQRI
bus voltage abnormality
(1) Replace the outdoor inverter
p.c. board
(1) Defective fan motor
(2) Defective outdoor inverter
p.c. board
2YHUKHDWRI,QYHUWHUSFERDUG
temperature
Ɣ'HWHFWLRQPHWKRG%RDUG
temperature thermistor at 80°C
or more detected for 1 second
(1) Defective fan motor
(2) Replace outdoor inverter p.c.
board

times

times
(1) Defective connector (CN664)
connection
(2) Defective (TH4)
a) Thermistor (TH4) disconnec-
tion
b) Thermistor (TH4) short circuit
(3) Defective outdoor inverter p.c.
board
6KRUWFLUFXLWRUGLVFRQQHFWLRQRI
hot water temp. thermistor（TH4）
Ɣ'HWHFWLRQPHWKRG'LVFRQQHF-
tion or short circuit detected
Ɣ'LVFRQQHFWLRQ°C or less
continued for 1 second 10
minutes onwards after start of
compressor operation
Ɣ6KRUWFLUFXLW°C or less
continued for 1 second at all
times
Ɣ&RQQHFWRU&1
(1) Connect connector (CN664)
(2) Check the resistance value
and temperature of thermistor
(TH4).
6HH+2:72&+(&.7+(
3$576
a) Replace thermistor (TH4)
b) Replace thermistor (TH4)
(3) Replace the outdoor inverter
p.c. board

GHH15010 12
Abnormal point and
detection method
CaseCheck Code
Check LED
LED2
RED
4
times
4
times
LED1
GREEN
Judgment and action
U1
(1) Water is not being circulated
in the outdoor unit water circuit
a) Cylinder unit not filled with
water
b) Air trapped in water pipes
c) Water leakage, crushing or
blockage of water pipes
d) Isolating valve in water pipes
closed
e) Pump valve in cylinder unit
closed
f) Water pipe freezing
g) Outdoor unit gas cooler
blockage
(2) Pump1 in the cylinder unit not
operating
a) Defective pump1
b) Defective cylinder unit board
(3) Defective LEV control caused
by erroneous detection of
discharge temperature
a) Discharge temperature
thermistor (TH1) loose from
discharge pipe
b) Defective discharge tempera-
ture thermistor (TH1)
(4) Defective LEV coil
a) Loose LEV coil
b) Loose connector [CN724]
c) LEV coil disconnection
(5) High pressure switch
malfunction or erroneous
detection
a) Loose connector [CN934],
defective contact
b) Loose high pressure switch
terminal, defective contact
c) Lead wire disconnection
(6) Defective outdoor inverter p.c.
board
(7) Defective coolant circuit parts
a) Defective high pressure switch
b) Defective LEV
Excessive high pressure
Ɣ'HWHFWLRQPHWKRG2SHUDWLRQ
of high pressure switch (HPS)
detected.
Ɣ(UURUFDQFHOODWLRQPHWKRG
This error is canceled by
turning the earth leakage circuit
breaker of the Cylinder Unit to
"OFF". To restart the outdoor
inverter, first check that the
LEDs (red/green) of the outdoor
inverter P.C. board are out,
(this takes approx. 1 minute),
turn the earth leakage circuit
breaker to "ON" again.
Check the following items.
To cancel this error, turn the earth
leakage circuit breaker of the
Cylinder Unit to "OFF" and then
back "ON" again.
2SHUDWLQJSUHVVXUH03D
FRQWDFWW\SH1&
FRQQHFWRU&1
(1) Check the water circuit, and
correct any abnormal locations
a) Fill with water
b) Bleed air
c) Correct or replace the water
piping
d) Repair the isolating valve
e) Repair the pump valve
I0HOWIUR]HQVHFWLRQV
g) Replace the outdoor unit
(2) Check pump1 in the cylinder
unit.
a) Replace pump1
b) Replace cylinder unit board
(3) Check the discharge
temperature thermistor
a) Install the discharge tempera-
ture thermistor (TH1) to the
discharge piping
E0HDVXUHWKHUHVLVWDQFHYDOXH
of the discharge temperature
thermistor (TH1).
(See "9-4. HOW TO CHECK THE
PARTS.")
Replace the discharge
temperature thermistor
(4) Check the LEV level.
(See "9-4. HOW TO CHECK THE
PARTS.")
a) Install LEV coil
b) Connect connector (CN724)
c) Replace LEV coil
(5) Check high pressure switch,
and repair malfunctions
a) Connect connector (CN934)
b) Repair connections
c) Replace lead wire
(6) Replace outdoor inverter p.c.
board
(7) Replace outdoor unit
Lit 8
times
Lit 9
times
(1) Defective outdoor inverter
p.c. board
Abnormality of compressor
phase current
Ɣ'HWHFWLRQPHWKRG'HWHFWLRQRI
compressor current abnormality
(1) Replace the outdoor inverter
p.c. board
(1) Obstacle contacting propeller
fan
(2) Defective fan motor
a) Fan motor wiring disconnec-
tion
b) Fan motor locked
(3) Defective outdoor inverter
p.c. board
Fan cutoff
Ɣ'HWHFWLRQPHWKRG'HWHFWLRQRI
fan motor abnormality
(1) Remove obstacle
(2) Replace fan motor
(See "9-4. HOW TO CHECK THE
PARTS.")
(3) Replace outdoor inverter p.c.
board
E6
or
None

GHH15010 13
Abnormal point and
detection method
CaseCheck Code
Check LED
LED2
RED
LED1
GREEN
Judgment and action
1
times Lit
6
times Lit
8
times
8
times
U2
U3
(1) Water is not being circulated
in the outdoor unit water circuit
a) Cylinder unit not filled with
water
b) Air trapped in water pipes
c) Water leakage, crushing or
blockage of water pipes
d) Isolating valve in water pipes
closed
e) Pump valve in cylinder unit
closed
f) Water pipe freezing
g) Outdoor unit gas cooler
blockage
(2) Pump1 in the cylinder unit not
operating
a) Defective pump1
b) Defective cylinder unit board
(3) Erroneous detection caused
by defective discharge
temperature thermistor (TH1)
(4) Defective LEV coil
a) Loose LEV coil
b) Loose connector (CN724)
c) LEV coil disconnection
(5) Defective coolant circuit part
a) Defective LEV
b) Insufficient coolant caused by
coolant leakage
Overheat discharge temperature
Ɣ'HWHFWLRQPHWKRG
THERMO_ASSY DIS detects
130°C or higher
(1) Check the water circuit, and
correct any abnormal locations
a) Fill with water
b) Bleed air
c) Correct or replace the water
piping
d) Repair the isolating valve
e) Repair the pump valve
f) Melt frozen sections
g) Replace the outdoor unit
(2) Check pump1 in the cylinder
unit.
a) Replace pump1
b) Replace cylinder unit board
(3) Measure the resistance value
of the discharge temperature
thermistor (TH1).
(See "9-4. HOW TO CHECK THE
PARTS.")
Replace the discharge tempera-
ture thermistor (TH1)
(4) Check LEV coil.
(See "9-4. HOW TO CHECK THE
PARTS.")
a) Install LEV coil
b) Connect connector (CN724)
c) Replace LEV coil
(5) Replace outdoor unit
(1) Refrigerant leakage on
refrigerant circuit
a) Evaporator breakage
b) Evaporator corrosion
c) Refrigerant piping damage
d) Refrigerant piping corrosion
e) Gas cooler damage
f) Gas cooler corrosion
(2) Defective compressor
compression
Refrigerant zero abnormality
Ɣ'HWHFWLRQPHWKRG'HWHFWHGE\
secondary current value at
startup operation
(1)-(2) Replace outdoor unit
(1) Defective connector (CN641)
connection
(2) Defective (TH1)
a) Thermistor (TH1) disconnec-
tion
b) Thermistor (TH1) short circuit
(3) Defective outdoor inverter p.c.
board
Short circuit or disconnection of
discharge temp.thermistor (TH1)
Ɣ'HWHFWLRQPHWKRG'LVFRQQHF-
tion or short circuit detected
Ɣ'LVFRQQHFWLRQ°C or less
continued for 2 minutes 10
minutes onwards after start of
compressor operation
Ɣ6KRUWFLUFXLW°C or less
continued for 2 minutes at all
times
Ɣ&RQQHFWRU&1
(1) Connect connector (CN641)
(2) Check the resistance value
and temperature of the
thermistor (TH1).
(See "9-4. HOW TO CHECK THE
PARTS.")
a) Replace thermistor (TH1)
b) Replace thermistor (TH1)
(3) Replace the outdoor inverter
p.c. board

GHH15010 14
Abnormal point and
detection method
CaseCheck Code
Check LED
LED2
RED
LED1
GREEN
Judgment and action
9
times
9
times
10
times
10
times
4
times
5
times
5
times
U4
(1) Defective connector (CN641)
connection
(2) Defective (TH2)
a) Thermistor (TH2) disconnec-
tion
b) Thermistor (TH2) short circuit
(3) Defective outdoor inverter p.c.
board
Ɣ'HWHFWLRQPHWKRG'LVFRQQHF-
tion or short circuit detected
Ɣ'LVFRQQHFWLRQ°C or less
continued for 2 minutes at start
of compressor operation
Ɣ6KRUWFLUFXLW°C or more
continued for 2 minutes at all
times
Ɣ&RQQHFWRU&1
6KRUWFLUFXLWRUGLVFRQQHFWLRQRI
defrost temp. thermistor (TH2）(1) Connect connector (CN641)
(2) Check the resistance value
and temperature of the
thermistor (TH2).
6HH+2:72&+(&.7+(
3$576
a) Replace thermistor (TH2)
b) Replace thermistor (TH2)
(3) Replace the outdoor inverter
p.c. board
(1) Defective connector (CN643)
connection
(2) Defective (TH3)
a) Thermistor (TH3) disconnec-
tion
b) Thermistor (TH3) short circuit
(3) Defective outdoor inverter p.c.
board
6KRUWFLUFXLWRUGLVFRQQHFWLRQRI
ambient temp. thermistor (TH3)
Ɣ'HWHFWLRQPHWKRG'LVFRQQHF-
tion or short circuit detected
Ɣ'LVFRQQHFWLRQ°C or less
detected for 2 minutes at start of
compressor operation
Ɣ6KRUWFLUFXLW°C or less
continued for 2 minutes at all
times
Ɣ&RQQHFWRU&1
(1) Connect connector (CN643)
(2) Check the resistance value
and temperature of the
thermistor (TH3).
6HH+2:72&+(&.7+(
3$576
a) Replace thermistor (TH3)
b) Replace thermistor (TH3)
(3) Replace the outdoor inverter
p.c. board
(1) Defective board temperature
thermistor
'LVFRQQHFWLRQRI2XWGRRULQYHUWHU
p.c. board temp. thermistor
Ɣ'HWHFWLRQPHWKRG'LVFRQQHF-
tion or short circuit detected
Ɣ'LVFRQQHFWLRQ'LVFRQQHFWLRQ
continued for 2 minutes from 1
minute onwards after start of
compressor operation
Ɣ6KRUWFLUFXLW6KRUWFLUFXLW
continued for 2 minutes at all
times
Ɣ&RQQHFWRU1RQH%RDUG
mounting
(1) Replace the outdoor inverter
p.c. board
(1) Defective connector (CN664)
connection
(2) Defective (TH4)
a) Thermistor (TH4) disconnec-
tion
b) Thermistor (TH4) short circuit
(3) Defective outdoor inverter p.c.
board
6KRUWFLUFXLWRUGLVFRQQHFWLRQRI
hot water temp. thermistor（TH4）
Ɣ'HWHFWLRQPHWKRG'LVFRQQHF-
tion or short circuit detected
Ɣ'LVFRQQHFWLRQ°C or less
continued for 2 minutes 10
minutes onwards after start of
compressor operation
Ɣ6KRUWFLUFXLW°C or less
continued for 2 minutes at all
times
Ɣ&RQQHFWRU&1
(1) Connect connector (CN664)
(2) Check the resistance value
and temperature of thermistor
(TH4).
6HH+2:72&+(&.7+(
3$576
a) Replace thermistor (TH4)
b) Replace thermistor (TH4)
(3) Replace the outdoor inverter
p.c. board
2XW

GHH15010 15
Abnormal point and
detection method
CaseCheck Code
Check LED
LED2
RED
LED1
GREEN
Judgment and action
2
times
Out
2
times
Out
Out
6
times
UP
2
times
EC
(1) Defective compressor lead
wire relay connector connection
a) Defective compressor relay
connector connection
b) Defective compressor terminal
connection
(2) Defective outdoor inverter
p.c. board
a) Defective Q821
b) Defective IC700
c) Defective overcurrent
detection circuit
(3) Defective LEV coil
a) Loose LEV coil
b) Loose connector [CN724]
c) LEV coil disconnection
(4) Defective LEV unit
a) LEV locked
b) Blocked with foreign matter
(5) Defective compressor
a) Compressor motor coil short
circuit, disconnection
b) Compressor locked
(6) Power waveform distortion,
noise
Overcurrent abnormality
Ɣ'HWHFWLRQPHWKRG2YHUFXUUHQW
detected by secondary current
(1) Check the continuity of the
compressor and lead wires.
a) Connect compressor relay
connector*
b) Connect compressor terminal*
(*Before correcting the problem,
turn the circuit breaker off.)
(2) Replace outdoor inverter p.c.
board
(3) Check LEV coil
(See "9-4. HOW TO CHECK
THE PARTS.")
a) Install LEV coil
b) Connect connector (CN724)
c) Replace LEV coil
(4)-(5) Replace outdoor unit
(6) Check to see if the power
waveform is normal
(1) Compressor relay connector
disconnected
(2) Defective outdoor inverter
p.c. board
Ɣ'HWHFWLRQPHWKRG6HUYLFH
mode* continued for 20 minutes
*The service mode is entered
when the outdoor unit is run with
the compressor relay connector
[CN61] disconnected. This
mode is used when measuring
the compressor drive voltage of
the outdoor inverter p.c. board.
Service mode end display (1) Turn the earth leakage circuit
breaker of the Cylinder Unit to
"OFF" before connecting the
compressor relay connector of
the outdoor unit.
(2) Replace the outdoor inverter
p.c. board
(1) Defective outdoor inverter
p.c. board
Ɣ'HWHFWLRQPHWKRG'HIHFWLYH
primary current detection sensor
detected continuously for 2
minutes
Abnormality of circuit to detect AC
current
(1) Replace the outdoor inverter
p.c. board
(1) Defective power transmission
line connection
(2) Defective outdoor inverter
p.c. board
(3) Defective cylinder unit control
board
(4) Noise
Start time exceeded
Ɣ'HWHFWLRQPHWKRG,QDELOLW\WR
receive communication detected
on outdoor unit microcomputer
(1) Correct power transmission
line connection
(2) Replace outdoor inverter p.c.
board
(3) Defective cylinder unit control
board
(4) Move power signal line away
from noise source

GHH15010 16
Abnormal point and
detection method
CaseCheck Code
Check LED
LED2
RED
LED1
GREEN
Judgment and action
Fd
(1) Low power supply voltage
a) Inappropriate power supply
used
b) Defective power transmission
line
c) Defective power transmission
line connection
(2) Erroneous operation of earth
leakage circuit breaker*
(3) Defective outdoor inverter p.c.
board
*When the earth leakage circuit
breaker of the Cylinder Unit is
turned to "OFF", the LEDs (red,
green) on the outdoor inverter
p.c. board go out. This,
however, takes about 1 minute.
While the LEDs on the outdoor
inverter p.c. board are lit, do not
turn the earth leakage circuit
breaker back on. Doing so
might cause this abnormality to
be detected again.
Ɣ'HWHFWLRQPHWKRG,QSXW
voltage to outdoor unit 70 V or
less
Detection of abnormal AC voltage (1) Check the power supply
voltage
a) Use a power supply having the
appropriate voltage
b) Replace the power transmis-
sion line
c) Correct the power transmission
line connection
(2) Perform a reset
(3) Replace the outdoor inverter
p.c. board
E6/E7/
E8/E9
Conti
nuous
blinking
Conti
nuous
blinking
FC
(1) Defective outdoor inverter
p.c. board
Abnormality in outdoor unit control
system
Ɣ'HWHFWLRQPHWKRG'HWHFWHG
on outdoor unit microcomputer
(1) Replace the outdoor inverter
p.c. board
(1) Defective power transmission
line between cylinder unit and
outdoor unit
a) Not connected
b) Disconnection
c) Defective contact
(2) Defective cylinder unit board
(3) Defective outdoor inverter
p.c. board
Communication abnormality
between cylinder unit and outdoor
unit
Ɣ'HWHFWLRQPHWKRG5HFHSWLRQ
malfunction detected on cylinder
unit microcomputer and outdoor
unit microcomputer
(1) Check the power transmis-
sion line between cylinder unit
and outdoor unit
a) Connect power transmission
line
b) Replace power transmission
line
c) Correct power transmission
line connection
(2) Replace cylinder unit board
(3) Replace outdoor inverter p.c.
board
2
times
2
times
11
times
11
times

GHH15010 17
1
times
3
times
5
times
6
times
7
times
8
times
10
times
11
times
12
times
Abnormal point and
detection method
CaseCheck Code
Check LED
LED2
RED
LED1
GREEN
Judgment and action
--
--
--
--
--
Discharge temperature high
temperature protection operation
in progress
Ambient air protection operation in
progress
Primary current protection in
operation
(compressor speed reduced)
Primary current protection in
operation
(compressor speed does not
increase)
Secondary stall control in progress
Propeller fan drive obstruction
a) Strong winds outside -(automatic recovery performed)
Fan protection stopped
(Compressor does not stop)
(1) Transient power supply
waveform distortion, noise
(2) Persistent power supply
waveform distortion, noise
(3) Defective outdoor inverter p.c.
board
(1) - (automatic recovery
performed)
(2) Check power supply waveform
(3) Replace outdoor inverter p.c.
board
PAM control stop in progress
(1) Transient power supply
waveform distortion, noise
(2) Persistent power supply
waveform distortion, noise
(3) Defective outdoor inverter p.c.
board
(1) - (automatic recovery
performed)
(2) Check to see if the power
waveform is normal
(3) Replace outdoor inverter p.c.
board
Primary voltage detection error
protection
(1) Compressor relay connector
disconnected
(2) Defective outdoor inverter p.c.
board
(1) Turn the earth leakage circuit
breaker of the Cylinder Unit to
"OFF" before connecting the
compressor relay connector of
the outdoor unit.
(2) Replace the outdoor inverter
p.c. board
Service mode*
*The service mode is entered
when the outdoor unit is run with
the compressor relay connector
disconnected.
Outdoor unit emergency stop
Lit
Lit
Lit
Lit
Lit
Lit
Lit
Lit
Lit
E6
or
None

GHH15010 18
1
2
3
4
5
6
M
red
blue
orange
yellow
white
Parts name Check points
Disconnect the connector then measure the resistance with a tester.
(At the ambient temperature of 10 to 30°C)
TH1 : Discharge temp.
TH2 : Defrost temp.
TH3 : Ambient temp.
TH4 : Hot water temp. Normal
WRNȍ
7.5 to 21 kȍ
TH1
TH4
TH2
TH3
Abnormal
Open or short
Open or short
Measure the resistance between the contacts of CN932 with a tester.
(At the ambient temperature of 20°C)
Compressor
(MC)
Normal Abnormal
Open or short
Disconnect the connector then measure the resistance with a tester.
Normal
Short
Abnormal
Open
High pressure switch
(HPS)
Fan motor (MF)
37.0 ± 1.33 ȍ
Normal Abnormal
Open or short12.8 ± 0.07 ȍ
Measure the resistance between the terminals with a tester.
(At the ambient temperature of 20°C)
W
V
U
Linear expansion valve
(LEV) Disconnect the connector then measure the resistance with a tester.
(Winding temperature 20°C)
Normal
red - blue red - orange red - yellow red - white
Abnormal
46 ± 4 
Open or short
7-4. HOW TO CHECK THE PARTS
1
2
3

GHH15010 19
500
400
300
200
100
04020060 80 100 120
Resistance (kȍ)
Temperature (°C)
0
50
60
70
80
90
40
30
20
10
100
110
120
130
140
150
-20-30 -10 0 10 20 30 40 50 60
Resistance (kȍ)
Temperature (°C)
7-5. HOW TO CHECK THE COMPONENTS
<Thermistor feature chart>
Low temperature thermistors
Thermistor <Defrost> (TH2)
Thermistor R0 = 33.18 Nȍ ± 2%
B constant = 3900 ± 3%
Rt=33.18exp{3900( 273+t – 273 )}
1
Thermistor R100 = Nȍ ± 2%
B constant = 4014 ± 2%
Rt=13.36exp{4014( 273+t – 373)}
11
High temperature thermistors
Thermistor <Discharge> (TH1)
Thermistor <Hot water> (TH4)
1
0°C 33 Nȍ
10°C 20 Nȍ
20°C 13 Nȍ
25°C 10 Nȍ
30°C 8.0 Nȍ
40°C 5.3 Nȍ
20°C 250 Nȍ
30°C 161 Nȍ
40°C 107 Nȍ
50°C 72 Nȍ
60°C 50 Nȍ
70°C 35 Nȍ
80°C 25 Nȍ
90°C 18 Nȍ
100°C 13 Nȍ
110°C 9.9 Nȍ

GHH15010 20
0
50
60
70
80
90
40
30
20
10
100
110
120
130
140
150
-20-30 -10 0 10 20 30 40 50 60
Resistance (kȍ)
Temperature (°C)
Low temperature thermistors
Thermistor <Ambient> (TH3)
Thermistor R0 = 33.18 Nȍ ± 2%
B constant = 3873 ± 2%
Rt=33.18exp{3873( 273+t – 273 )}
11
0°C 33 Nȍ
10°C 20 Nȍ
20°C 13 Nȍ
25°C 10 Nȍ
30°C 8.0 Nȍ
40°C 5.4 Nȍ
LEV
M1
2
red
blue
orange
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CN724
12 V DC
Inverter p.c. board
Drive circuit
Linear expansion valve
< Connection between the inverter p.c. board and the expansion valve >