Mitsubishi Electric Mr. Slim SUZ-KA25VA6 Operating manual

TECHNICAL & SERVICE MANUAL
R410A
[Model Name]
SUZ-KA25VA6
SUZ-KA35VA6
SUZ-KA50VA6
SUZ-KA60VA6
SUZ-KA71VA6
CONTENTS
1. COMBINATION OF INDOOR AND OUTDOOR UNITS
..... 2
2. PARTS NAMES AND FUNCTIONS .................. 3
3. SPECIFICATION................................................ 4
4. NOISE CRITERIA CURVES.............................. 6
5. OUTLINES AND DIMENSIONS ........................ 7
6. WIRING DIAGRAM............................................ 9
7. REFRIGERANT SYSTEM DIAGRAM............. 12
8. ACTUATOR CONTROL................................... 16
9. SERVICE FUNCTIONS ................................... 17
10. TROUBLESHOOTING..................................... 17
11. DISASSEMBLY PROCEDURE........................ 34
Indication of
model name
Note:
•This service manual
describes service data of
the outdoor units only.
HFC
utilized
R410A
SUZ-KA25VA6.TH
SUZ-KA35VA6.TH
PARTS CATALOG (TCB004)
No. TCH004
November 2016
SPLIT-TYPE, HEAT PUMP AIR CONDITIONERS
[Service Ref.]
SUZ-KA25VA6.TH SUZ-KA25VA6.TH-ER
SUZ-KA25VA6.TH-ET
SUZ-KA35VA6.TH SUZ-KA35VA6.TH-ER
SUZ-KA35VA6.TH-ET
SUZ-KA50VA6.TH SUZ-KA50VA6.TH-ER
SUZ-KA50VA6.TH-ET
SUZ-KA60VA6.TH SUZ-KA60VA6.TH-ER
SUZ-KA60VA6.TH-ET
SUZ-KA71VA6.TH SUZ-KA71VA6.TH-ER
SUZ-KA71VA6.TH-ET

2
TCH004
1COMBINATION OF INDOOR AND OUTDOOR UNITS
INDOOR UNIT SERVICE MANUAL
Indoor unit Outdoor unit Heat pump type
SUZ-
Service Ref. Service
manual No.
KA25VA6.TH
KA25VA6.TH-ER
KA25VA6.TH-ET
KA35VA6.TH
KA35VA6.TH-ER
KA35VA6.TH-ET
KA50VA6.TH
KA50VA6.TH-ER
KA50VA6.TH-ET
KA60VA6.TH
KA60VA6.TH-ER
KA60VA6.TH-ET
KA71VA6.TH
KA71VA6.TH-ER
KA71VA6.TH-ET
Heat pump without electric heater
SLZ-KF25VA2.TH(-ER) OCH616
OCB616
────
SLZ-KF35VA2.TH(-ER) ─ ───
SLZ-KF50VA2.TH(-ER) ── ──
SLZ-KF60VA2.TH(-ER) ─── ─
SEZ-KD25VAQR2.TH(-ER) HWE1008
BWE102040
(BWE014090)
────
SEZ-KD35VAQR2.TH(-ER) ─ ───
SEZ-KD50VAQR2.TH(-ER) ── ──
SEZ-KD60VAQR2.TH(-ER) ─── ─
SEZ-KD71VAQR2.TH(-ER) ────
SEZ-KD25VALR2.TH
HWE0711
BWE012050
────
SEZ-KD35VALR2.TH ─ ───
SEZ-KD50VALR2.TH ── ──
SEZ-KD60VALR2.TH ─── ─
SEZ-KD71VALR2.TH ────
PLA-RP35EA.UK OCH625
OCB625
─ ───
PLA-RP50EA.UK ── ──
PLA-RP60EA.UK ─── ─
PLA-RP71EA.UK ────
PCA-RP35KAQR2(-ER) OCH491
OCB491
─ ───
PCA-RP50KAQR2(-ER) ── ──
PCA-RP60KAQR2(-ER) ─── ─
PCA-RP71KAQR2(-ER) ────
PEAD-RP35JAQR2.UK
BWE014160
─ ───
PEAD-RP50JAQR2.UK ── ──
PEAD-RP60JAQR2.UK ─── ─
PEAD-RP71JAQR2.UK ────
PEAD-RP35JALQR2.UK ─ ───
PEAD-RP50JALQR2.UK ── ──
PEAD-RP60JALQR2.UK ─── ─
PEAD-RP71JALQR2.UK ────

3
TCH004
2PARTS NAMES AND FUNCTIONS
SUZ-KA25VA6
SUZ-KA35VA6
SUZ-KA50VA6
SUZ-KA60VA6
SUZ-KA71VA6
Air outlet
Drain outlet
Piping
Drain hose
Air inlet
(back and side)
Model SUZ-KA·VA6
Drain socket 1
Piping
Air outlet
Drain outlet
Air inlet
(back and side)
Drain hose

4
TCH004
SPECIFICATION
3
Note: Test conditions are based on JIS B8616
Cooling : Indoor D.B. 27°C W.B. 19°C
Outdoor D.B. 35°C
Heating : Indoor D.B. 20°C
Outdoor D.B. 7°C W.B. 6°C
Refrigerant piping length (one way): 7 m
*Measured under rated operating frequency.
Outdoor model
SUZ-KA25VA6 SUZ-KA35VA6 SUZ-KA50VA6 SUZ-KA60VA6 SUZ-KA71VA6
Power supply Single phase 230 V, 50 Hz
Compressor
Model KNB073FKFMC KNB092FFAMC SNB130FGBMT SNB172FEKMT
Output W 550 650 900 1,200
Current* Cooling A2.76 4.06 5.58 6.62 8.02
Heating 3.24 4.09 5.75 6.37 8.13
Refrigeration oil
(Model)
L 0.31 (FV50S) 0.27 (FV50S) 0.35 (FV50S) 0.4 (FV50S)
Fan motor Model RC0J50-NA RC0J60-BC RC0J60-BC
Current* Cooling A0.24 0.29 0.84 0.84 0.83
Heating 0.27 0.28 0.93 0.93 0.82
Dimensions W × H × D mm 800 × 550 × 285 840 × 880 × 330
Weight kg 30 35 54 50 53
Special remarks
Air
flow*
Cooling High
m³/h
1,806 2,868 3,492 3,426
Med. 1,806 2,868 3,066 3,006
Low 1,170 1,038 1,602 1,692 1,512
Heating High 2,106 2,778 2,952 2,892 Med. 1,806 1,770 2,778 2,952 2,892
Low 1,452 1,326 2,124 2,226 2,280
Sound pressure level*
Cooling
dB(A)
47 49 52 55
Heating 48 50 52 55
Sound power level 58 62 65 65 69
Fan
speed
Cooling High
rpm
740 810 840 950
Med. 740 810 840
Low 740 490 480 450
Heating High 860 900 810 Med. 740 770 810
Low 600 610 620 650
Fan speed regulator 3
Refrigerant filling capacity
(R410A) kg 0.80 1.15 1.60 1.60 1.80

5
TCH004 5
Specifications and rating conditions of main electric parts
Model
Item
SUZ-KA25VA6 SUZ-KA35VA6 SUZ-KA50VA6 SUZ-KA60VA6 SUZ-KA71VA6
Smoothing
capacitor
(C61) — — 620 μF 420 V — —
(C62, C63) 620 μF 420 V 620 μF 420 V 620 μF420 V — —
(CB1, 2, 3) — — — 560 μF 450 V 560 μF 350 V
Diode module (DB61) 15 A 600 V 15 A 600 V 25 A 600 V — —
Fuse
(F61) T20 A L250 V T20 A L250 V T20 A L250 V — —
(F62) — — — T20A L250V T20A L250V
(F701, F801, F901) T3.15 A L250 V T3.15 A L250 V T3.15 A L250 V — —
(IC700) 15 A 600 V 15 A 600 V 20 A 600 V — —
Inteligent power
module (IPM) — — — 20 A 600 V
(IC932) 8 A 600 V 8 A 600 V 8 A 600 V 5 A 600 V 5 A 600 V
Power factor
controller (PFC) — — — 20A 600V 20A 600V
(IC820) 20 A 600 V 20 A 600 V 20 A 600 V — —
Expansion valve
coil (LEV) 12 V DC
Reactor (L61) 18 mH 23 mH 23 mH — —
(L) — — — 340 μH 20 A 340 μH 20 A
Current-Limiting
PTC thermistor (PTC64, PTC65) 33Ω
Terminal block (TB1, TB2) — — — 3P 3P
(TB) 5P 5P 5P — —
Relay
(X63) 3 A 250 V 3 A 250 V 3 A 250 V — —
(X64) 20 A 250 V
(X601) — — — 3 A 250 V 3 A 250 V
(X602) — — — 3 A 250 V 3 A 250 V
R.V. coil (21S4) 220–240 V AC

6
TCH004
NOISE CRITERIA CURVES
4
OCTAVE BAND SOUND PRESSURE LEVEL, dB re 0.0002 MICRO BAR
COOLING
FUNCTION SPL(dB(A)) LINE
High
Med.
FAN SPEED
HEATING
47
48
90
80
70
60
50
40
30
20
10 63 125 250 500 1000 2000 4000 8000
NC-60
NC-50
NC-40
NC-30
NC-20
NC-70
BAND CENTER FREQUENCIES, Hz
NC-10
SUZ-KA25VA6.TH
SUZ-KA25VA6.TH-ER
SUZ-KA25VA6.TH-ET
OCTAVE BAND SOUND PRESSURE LEVEL, dB re 0.0002 MICRO BAR
COOLING
FUNCTION SPL(dB(A)) LINE
FAN SPEED
HEATING
49
50
High
Med.
90
80
70
60
50
40
30
20
10 63 125 250 500 1000 2000 4000 8000
NC-60
NC-50
NC-40
NC-30
NC-20
NC-70
BAND CENTER FREQUENCIES, Hz
NC-10
SUZ-KA35VA6.TH
SUZ-KA35VA6.TH-ER
SUZ-KA35VA6.TH-ET
COOLING
FUNCTION SPL(dB(A)) LINE
High
FAN SPEED
HEATING
52
52
OCTAVE BAND SOUND PRESSURE LEVEL, dB re 0.0002 MICRO BAR
90
80
70
60
50
40
30
20
10 63 125 250 500 1000 2000 4000 8000
NC-60
NC-50
NC-40
NC-30
NC-20
NC-70
BAND CENTER FREQUENCIES, Hz
NC-10
SUZ-KA50VA6.TH
SUZ-KA50VA6.TH-ER
SUZ-KA50VA6.TH-ET
Test conditions
Cooling: Dry-bulb temperature 35°C
Heating: Dry-bulb temperature 7°C
Wet-bulb temperature 6°C
OUTDOOR UNIT
MICROPHONE
1 m
SUZ-KA60VA6.TH SUZ-KA71VA6.TH
SUZ-KA60VA6.TH-ER SUZ-KA71VA6.TH-ER
SUZ-KA60VA6.TH-ET SUZ-KA71VA6.TH-ET
OCTAVE BAND SOUND PRESSURE LEVEL, 0dB re 0.0002 MICRO BAR
COOLING
FUNCTION SPL(dB(A)) LINE
High
FAN SPEED
HEATING
55
55
90
80
70
60
50
40
30
20
10 63 125 250 500 1000 2000 4000 8000
NC-60
NC-50
NC-40
NC-30
NC-20
NC-70
BAND CENTER FREQUENCIES, Hz
NC-10

7
TCH004
5OUTLINES AND DIMENSIONS
10
69
800
302.5
500 Bolt pitch for installation
150
22.3
Handle
550
280
164.5
99.5
170.5
23 Service panel
Service port
285
344.5
44
400
Air in
Air out
Air in
17.5
Bolt pitch for
installation
304~325
40
Liquid refrigerant pipe joint
Refrigerant pipe (flared) [6.35
Gas refrigerant pipe joint
Refrigerant pipe (flared) [9.52
43-
35-
2-Oval holes 10×21
REQUIRED SPACE
Basically, leave this space open.
Only if front and both sides are open,
leave 100 mm at minimum.
350mm or more
200mm or more
100mm or more
100mm or more
200 mm or more.
Leave any 2 sides among
right, left or rear open.
Drain hole [42
Unit: mm
SUZ-KA25VA6.TH SUZ-KA35VA6.TH
SUZ-KA25VA6.TH-ER SUZ-KA35VA6.TH-ER
SUZ-KA25VA6.TH-ET SUZ-KA35VA6.TH-ET

8
TCH004
417.5
40
42
Drain hole
175 500
330
50
Air in
Air out 2-Oval holes 10 21
840
109 81
880
452
Service panel
99.5
164.5
195
35
44
Liquid refrigerant pipe joint
Refrigerant pipe (flared)
Ø 6.35...(SUZ-KA50/60VA6)
Ø 9.52...(SUZ-KA71VA6)
Gas refrigerant pipe joint
Refrigerant pipe (flared)
Ø 12.7...(SUZ-KA50VA6)
Ø 15.88...(SUZ-KA60/71VA6)
350 mm or more
100 mm or more
REQUIRED SPACE
Basically, leave this space open.
Only if front and both sides are open,
leave 500 mm at minimum.
100mm or more
500 mm or more.
Leave any 2 sides among
right, left or rear open.
Air in
Bolt pitch for
installation
360
Unit: mm
SUZ-KA50VA6.TH SUZ-KA60VA6.TH SUZ-KA71VA6.TH
SUZ-KA50VA6.TH-ER SUZ-KA60VA6.TH-ER SUZ-KA71VA6.TH-ER
SUZ-KA50VA6.TH-ET SUZ-KA60VA6.TH-ET SUZ-KA71VA6.TH-ET

9
TCH004 9
6WIRING DIAGRAM
SUZ-KA25VA6.TH SUZ-KA35VA6.TH
SUZ-KA25VA6.TH-ER SUZ-KA35VA6.TH-ER
SUZ-KA25VA6.TH-ET SUZ-KA35VA6.TH-ET

10
TCH004
SUZ-KA50VA6.TH
SUZ-KA50VA6.TH-ER
SUZ-KA50VA6.TH-ET

11
TCH004
SUZ-KA60VA6.TH SUZ-KA71VA6.TH
SUZ-KA60VA6.TH-ER SUZ-KA71VA6.TH-ER
SUZ-KA60VA6.TH-ET SUZ-KA71VA6.TH-ET

12
TCH004
REFRIGERANT SYSTEM DIAGRAM
7
Unit: mm
SUZ-KA25VA6.TH
SUZ-KA25VA6.TH-ER
SUZ-KA25VA6.TH-ET
Unit: mm
SUZ-KA35VA6.TH
SUZ-KA35VA6.TH-ER
SUZ-KA35VA6.TH-ET
Flared connection
Defrost
thermistor
RT61
Discharge
temperature
thermistor
RT62
Flared connection
Stop valve
(with strainer)
Stop valve
(with service port)
Refrigerant flow in cooling
Compressor
4-way valve
Refrigerant flow in heating
Refrigerant pipe ø9.52
(with heat insulator)
Refrigerant pipe ø6.35
(with heat insulator)
R.V. coil
heating ON
cooling OFF
Strainer
#100
Ambient
temperature
thermistor
RT65
Muffler
Capillary tube
ø3.0×ø2.0×240
Outdoor heat
exchanger
temperature
thermistor
RT68
Muffler
Outdoor
heat
exchanger
LEV
Outdoor
heat
exchanger
Flared connection
Defrost
thermistor
RT61
Discharge
temperature
thermistor
RT62
Flared connection
Stop valve
(with strainer)
Stop valve
(with service port)
Refrigerant flow in cooling
Compressor
4-way valve
Refrigerant flow in heating
Refrigerant pipe ø9.52
(with heat insulator)
Refrigerant pipe ø6.35
(with heat insulator)
R.V. coil
heating ON
cooling OFF
Strainer
#100
Capillary tube
ø3.0×ø1.8×600(×2)
LEV
Ambient
temperature
thermistor
Muffler
Capillary tube
ø3.0×ø2.0×240
Outdoor heat
exchanger
temperature
thermistor
Muffler
RT65
RT68

13
TCH004 13
Unit: mm
Unit: mm
SUZ-KA50VA6.TH
SUZ-KA50VA6.TH-ER
SUZ-KA50VA6.TH-ET
SUZ-KA60VA6.TH
SUZ-KA60VA6.TH-ER
SUZ-KA60VA6.TH-ET
Outdoor
heat
exchanger
Flared connection
Defrost
thermistor
RT61
Discharge
temperature
thermistor
RT62
Flared connection
Stop valve
Stop valve
(with service port)
Capillary tube
ø 4.0 × ø 2.4 × 100 Refrigerant flow in cooling
Compressor
4-way valve
Refrigerant flow in heating
Refrigerant pipe
ø 12.7
(with heat insulator)
Refrigerant pipe ø 6.35
(with heat insulator)
LEV R.V. coil
heating ON
cooling OFF
Muffler
Strainer
#100
Outdoor heat
exchanger
temperature
thermistor
RT68
Ambient
temperature
thermistor
RT65
Strainer
#100
Strainer
#100
Muffler
Outdoor
heat
exchanger
Flared connection
Defrost
thermistor
RT61
Discharge
temperature
thermistor
RT62
Flared connection
Stop valve
Stop valve
(with service port)
Capillary tube
ø 4.0 × ø 2.4 × 100 Refrigerant flow in cooling
Compressor
4-way valve
Refrigerant flow in heating
Refrigerant pipe
ø 15.88
(with heat insulator)
Refrigerant pipe ø 6.35
(with heat insulator)
LEV R.V. coil
heating ON
cooling OFF
Muffler
Strainer
#100
Outdoor heat
exchanger
temperature
thermistor
RT68
Ambient
temperature
thermistor
RT65
Strainer
#100

14
TCH004
Unit: mm
SUZ-KA71VA6.TH
SUZ-KA71VA6.TH-ER
SUZ-KA71VA6.TH-ET
Outdoor
heat
exchanger
Flared connection
Defrost
thermistor
RT61
Discharge
temperature
thermistor
RT62
Flared connection
Stop valve
Stop valve
(with service port)
Capillary tube
ø 4.0 × ø 2.4 × 100 Refrigerant flow in cooling
Compressor
4-way valve
Refrigerant flow in heating
Refrigerant pipe
(with heat insulator)
ø 15.88
Refrigerant pipe
(with heat insulator)
LEV R.V. coil
heating ON
cooling OFF
Muffler
Strainer
#100
Outdoor heat
exchanger
temperature
thermistor
RT68
Ambient
temperature
thermistor
RT65
Strainer
#100
ø 9.52

15
TCH004
ADDITIONAL REFRIGERANT CHARGE (R410A: g)
MAX. REFRIGERANT PIPING LENGTH
Max. Length
A
* Height difference limitations are binding regardless of the height position at which either indoor or outdoor is placed higher.
* Max. Height
difference
B
Indoor
unit
Outdoor unit
MAX. HEIGHT DIFFERENCE
Calculation : Xg=20g/m×(Refrigerant piping length(m)−7)
Calculation : Xg=55g/m×(Refrigerant piping length(m)−7)
Model Outdoor unit
precharged Refrigerant piping length (one way)
7 m 8 m 9 m 10 m 11 m 12 m 13 m 14 m 15 m 20 m
SUZ-KA25VA6 800 0 30 60 90 120 150 180 210 240 390
SUZ-KA35VA6 1,150 0 30 60 90 120 150 180 210 240 390
Calculation: Xg=30g/m×(Refrigerant piping length(m)−7)
Model Refrigerant piping: m Piping size O.D: mm
Max. Length A
Max. Height difference B Gas Liquid
SUZ-KA25VA6 20 12 9.52 6.35
SUZ-KA35VA6
SUZ-KA50VA6 30 30 12.7
SUZ-KA60VA6 15.88
SUZ-KA71VA6 9.52
Model Outdoor unit
precharged Refrigerant piping length (one way)
7 m 10 m 15 m 20 m 25 m 30 m
SUZ-KA50VA6 1,600 0 60 160 260 360 460
SUZ-KA60VA6 1,600 0 60 160 260 360 460
Model Outdoor unit
precharged Refrigerant piping length (one way)
7 m 10 m 15 m 20 m 25 m 30 m
SUZ-KA71VA6 1,800 0 165 440 715 990 1,265
Pumping Down
When relocating or disposing of the air conditioner, pump down the system by following the procedure below so that no
refrigerant is released into the atmosphere.
1 Turn off the power supply (circuit breaker).
2Connect the gauge manifold valve to the service port of the stop valve on the gas pipe side of the outdoor unit.
3Fully close the stop valve on the liquid pipe side of the outdoor unit.
4Supply power (circuit breaker).
5 Perform the refrigerant collecting operation (cooling test run).
•
For the PAR-31MAA, select “Service” →“Test Run” from the main menu to start the test run, and then select the cooling mode.
• For details or for other information about starting the test run when using remote controllers, refer to the installation manual
for the indoor unit or the remote controller.
6 Fully close the stop valve on the gas pipe side of the outdoor unit when the pressure gauge shows 0.05 to 0 MPa [Gauge]
(approx. 0.5 to 0 kgf/cm²) and quickly stop the air conditioner.
• Push the “ON/OFF” button on the remote controller to stop the air conditioner.
Note:
When the extension piping is very long with a large refrigerant amount, it may not be possible to perform a pump down
operation. In this case, use refrigerant recovery equipment to collect all of the refrigerant in the system.
7 Turn off the power supply (circuit breaker), remove the gauge manifold valve, and then disconnect the refrigerant pipes.
.Warning: When pumping down the refrigerant, stop the compressor before disconnecting the refrigerant pipes.
• If the refrigerant pipes are disconnected while the compressor is operating and the stop valve (ball valve) is open,
the pressure in the refrigeration cycle could become extremely high if air is drawn in, causing the pipes to burst,
personal injury, etc.

16
TCH004
ACTUATOR CONTROL
8
8-3. RELATION BETWEEN MAIN SENSOR AND ACTUATOR
8-2. R.V. COIL CONTROL
Heating . . . . . . . . . . . . . . . . . ON
Cooling . . . . . . . . . . . . . . . . . OFF
Dry . . . . . . . . . . . . . . . . . . . . OFF
ON
OFF
ON
OFF
Outdoor fan
Compressor
5 seconds 15 seconds
ON
OFF
Compressor
Outdoor fan
motor
R.V.coil ON
OFF
ON
OFF
<COOL>
5 seconds
<HEAT>
5 seconds
8-1. OUTDOOR FAN MOTOR CONTROL
The fan motor turns ON/OFF, interlocking with the compressor.
[ON] The fan motor turns ON 5 seconds before the compressor starts up.
[OFF] The fan motor turns OFF 15 seconds after the compressor has stopped running.
NOTE: The 4-way valve reverses for 5 seconds
right before start-up of the compressor.
Sensor Purpose Actuator
Compressor LEV Outdoor fan
motor R.V.coil Indoor fan motor
Discharge temperature
thermistor Protection ○○
Indoor coil temperature
thermistor Cooling: Coil frost prevention ○
Heating: High pressure protection ○○
Defrost thermistor Heating: Defrosting ○○○○○
Fin temperature thermistor Protection ○○
Ambient temperature
thermistor Cooling: Low ambient temperature operation ○○○
Outdoor heat exchanger
temperature thermistor Cooling: Low ambient temperature operation ○○○
Cooling: High pressure protection ○○○
SUZ-KA25VA6.TH SUZ-KA35VA6.TH SUZ-KA50VA6.TH
SUZ-KA25VA6.TH-ER SUZ-KA35VA6.TH-ER SUZ-KA50VA6.TH-ER
SUZ-KA25VA6.TH-ET SUZ-KA35VA6.TH-ET SUZ-KA50VA6.TH-ET
SUZ-KA60VA6.TH SUZ-KA71VA6.TH
SUZ-KA60VA6.TH-ER SUZ-KA71VA6.TH-ER
SUZ-KA60VA6.TH-ET SUZ-KA71VA6.TH-ET

17
TCH004
CHANGE IN DEFROST SETTING
Changing defrost finish temperature
<JS> To change the defrost finish temperature, cut/solder the JS wire of the outdoor inverter P.C. board. (Refer to "10-6-1.
Inverter P.C. board".)
10 TROUBLESHOOTING
3. Troubleshooting procedure
1) Check if the OPERATION INDICATOR lamp on the outdoor P.C. board is blinking on and off to indicate an abnormal-
ity. To make sure, check how many times the abnormality indication is blinking on and off before starting service work.
2) Before servicing check that the connector and terminal are connected properly.
3) If the electronic control P.C. board is supposed to be defective, check the copper foil pattern for disconnection and the
components for bursting and discoloration.
4) When troubleshooting, refer to "10-2. TROUBLESHOOTING CHECK TABLE" and "10-3. HOW TO PROCEED "SELF-
DIAGNOSIS"".
10-1. CAUTIONS ON TROUBLESHOOTING
1. Before troubleshooting, check the following items:
1) Check the power supply voltage.
2) Check the indoor/outdoor connecting wire for miswiring.
2. Take care of the following during servicing.
1)
Before servicing the air conditioner, be sure to turn OFF the main unit first with the remote controller, and turn off the breaker.
2) Be sure to turn OFF the power supply before removing the front panel, the cabinet, the top panel, and the electronic
control P.C. board.
3) When removing the electrical parts, be careful of the residual voltage of smoothing capacitor.
4) When removing the electronic control P.C. board, hold the edge of the board with care NOT to apply stress on the
components.
5) When connecting or disconnecting the connectors, hold the housing of the connector. DO NOT pull the lead wires.
Housing point
Lead wire
9SERVICE FUNCTIONS
Jumper wire Defrost finish temperature (°C)
SUZ-KA25VA6 SUZ-KA35VA6 SUZ-KA50VA6 SUZ-KA60VA6
SUZ-KA71VA6
JS Soldered (Initial setting) 5 9 9 10
None (cut) 8 13 18 18
SUZ-KA25VA6.TH SUZ-KA35VA6.TH SUZ-KA50VA6.TH
SUZ-KA25VA6.TH-ER SUZ-KA35VA6.TH-ER SUZ-KA50VA6.TH-ER
SUZ-KA25VA6.TH-ET SUZ-KA35VA6.TH-ET SUZ-KA50VA6.TH-ET
SUZ-KA60VA6.TH SUZ-KA71VA6.TH
SUZ-KA60VA6.TH-ER SUZ-KA71VA6.TH-ER
SUZ-KA60VA6.TH-ET SUZ-KA71VA6.TH-ET
SUZ-KA25VA6.TH SUZ-KA35VA6.TH SUZ-KA50VA6.TH
SUZ-KA25VA6.TH-ER SUZ-KA35VA6.TH-ER SUZ-KA50VA6.TH-ER
SUZ-KA25VA6.TH-ET SUZ-KA35VA6.TH-ET SUZ-KA50VA6.TH-ET
SUZ-KA60VA6.TH SUZ-KA71VA6.TH
SUZ-KA60VA6.TH-ER SUZ-KA71VA6.TH-ER
SUZ-KA60VA6.TH-ET SUZ-KA71VA6.TH-ET

18
TCH004
temperature thermistor, outdoor heat exchanger temperature
No. Symptoms Abnormal point/
Condition RemedyCondition
1Outdoor unit
does not op-
erate.
1-time flash
every
2.5 seconds
Outdoor power sys-
tem Overcurrent protection cut-out operates 3 consecutive times
within 1 minute after the compressor gets started.
Reconnect connector of compressor.
Refer to 11-5. "How to check in-
verter/compressor".
Check stop valve.



2
Outdoor thermistors Discharge temperature thermistorshorts, or opens during
compressor running. defrost thermistor, P.C. board
thermistor or ambient temperature thermistor shorts, or opens
during compressor running.
Refer to 11-5.F"Check of outdoor
thermistors".

3
Outdoor control system
Nonvolatile memory data cannot be read properly. Replace inverter P.C. board.
46-time flash
2.5 seconds
OFF
Serial signal The communication fails between the indoor and outdoor unit
for 3 minutes.
511-time flash
2.5 seconds OFF
Stop valve/
Closed valve Closed valve is detected by compressor current. Check stop valve.

6

7'Outdoor unit
stops and
restarts 3
minutes later'
is repeated.
2-time flash
2.5 seconds OFF Overcurrent protec- tion Large current flows into intelligent power module.
Reconnect connector of compressor.
Refer to 11-5. "How to check in-
verter/compressor".
Check stop valve.



83-time flash
2.5 seconds OFF Discharge tempera- ture overheat pro-
tection
Temperature of discharge temperature thermistor exceeds
116°C, compressor stops. Compressor can restart if discharge
temperature thermistor reads 100°C or less 3 minutes later.
Check refrigerant circuit and refrig-
erant amount.
Refer to 11-5. "Check of LEV".


9
4-time flash
2.5 seconds OFF Fin temperature /P.C. board tem-
perature thermistor
overheat protection
Temperature of fin temperature thermistor on the heat sink
exceeds 72 to 86°C or temperature of P.C. board temperature
thermistor on the inverter P.C.board exceeds 72 to 85°C.
Check around outdoor unit.
Check outdoor unit air passage.
Refer to 11-5. "Check of outdoor
fan motor".



10 5-time flash
2.5 seconds OFF High pressure pro- tection Indoor coil thermistor exceeds 70°C in HEAT mode. Defrost thermistor exceeds 70°C in COOL mode. Check refrigerant circuit and refrig- erant amount.
Check stop valve.


11 8-time flash
2.5 seconds OFF Compressor syn- chronous abnormal-
ity
The waveform of compressor current is distorted.
Reconnect connector of compressor.
Refer to 11-5. "How to check in-
verter/compressor".


12 10-time flash
2.5 seconds OFF Outdoor fan motor Outdoor fan has stopped 3 times in a row within 30 seconds after outdoor fan start-up. Refer to 11-5. "Check of outdoor
fan motor.
Refer to 11-5. "Check of inverter
P.C. board.


13 12-time flash
2.5 seconds OFF Each phase current of compressor Each phase current of compressor cannot be detected nor- mally. Refer to 11-5. "How to check in- verter/compressor".

14 13-time flash
2.5 seconds OFF DC voltage DC voltage of inverter cannot be detected normally. Refer to 11-5. "How to check in- verter/compressor".

15 Outdoor unit operates. 1-time flash 2.5 seconds OFF Frequency drop by current protection
When the input current exceeds approximately 7A(KA25)/
8A(KA35)/12A(KA50)14A(KA60)/16A(KA71), compressor
The unit is normal, but check the
following.
Check if indoor filters are clogged.
Check if refrigerant is short.
Check if indoor/outdoor unit air
circulation is short cycled.



16
3-time flash
2.5 seconds OFF Frequency drop by high pressure pro-
tection
Temperature of indoor coil thermistor exceeds 55°C in HEAT
mode, compressor frequency lowers.
Frequency drop by
defrosting in COOL
mode
Indoor coil thermistor reads 8°C or less in COOL mode, com-
pressor frequency lowers.
17
4-time flash
2.5 seconds OFF Frequency drop by discharge tempera-
ture protection
Temperature of discharge temperature thermistor exceeds
111°C, compressor frequency lowers. Check refrigerant circuit and refrig- erant amount.
Refer to 11-5. "Check of LEV".
Refer to 11-5. "Check of outdoor
thermistors".



18
19
7-time flash
2.5 seconds OFF Low discharge tem- perature protection Temperature of discharge temperature thermistor has been 50°C or less for 20 minutes. Refer to 11-5. "Check of LEV". Check refrigerant circuit and refrig-
erant amount.


8-time flash
2.5 seconds OFF PAM protection
PAM: Pulse Ampli-
tude Modulation
The overcurrent flows into PFC (Power factor correction :
IC820) or the bus-bar voltage reaches 394 V or more, PAM
stops and restarts.
This is not malfunction. PAM pro-
tection will be activated in the fol-
lowing cases:
1. Instantaneous power voltage
drop. (Short time power failure)
2. When the power supply voltage
is high.
9-time flash
2.5 seconds OFF Inverter check mode The connector of compressor is disconnected, inverter check mode starts. Check if the connector of the com- pressor is correctly connected.
Refer to 11-5. "How to check
inverter/compressor".

Notes: 1. The location of LED is illustrated at the right figure. Refer to “11-6-1. Inverter P.C. board”.
2. LED is lighted during normal operation.
The flashing frequency shows the number of times the LED blinks after every 2.5-second OFF.
(Example) When the flashing frequency is “2”.
ON
OFF 2.5-second OFF 2.5-second OFF
0.5-second ON 0.5-second ON LED
Flashing ĺ
Inverter P.C. board

I
H
H
J
I
F
I

Check of indoor/outdoor connecting wire.
Replace indoor or outdoor P.C. board if
abnormality is displayed again.
(KA25/35/50)
(KA60/71)
Zerocross detecting
circuit
Zero cross signal for PAM control cannot be detected.
LED
indication
check
code
UP
U3
U4
FC
E8
E9
UE
Fin temperature thermistor,
/
frequency lowers.
16-time flash
2.5 seconds
OFF
PL
Outdoor refrigerant
system abnormality
A closed valve and air trapped in the refrigerant circuit are detected
based on the temperature sensed by the indoor and outdoor thermistors
and the current of the compressor.
 Check for a gas leak in a connecting
piping, etc.
Check stop valve.
Refer to 11-5
. L
refrigerant circuit”.
"Check of outdoor
20
10-2. TROUBLESHOOTING CHECK TABLE

19
TCH004
F1 F2 F3 F4
unemecivreS
rosruC :unemniaM
Test run
Input maintenance info.
Function setting
Check
Self check
kcehcfleS
:tceleS
Ref. address
sserddA
kcehcfleS
Ref. address
Return: teseR
Error Unt # CI.prG
Self check
Return: Reset
Ref. address
Error
-- Unt # Grp.
-- --
When there is no error history
Self check
Delete error history?
Ref. address
Cancel OK
Self check
Return:
Ref. address
Error history deleted
2
With the F1 or F2 button, enter the refrigerant address, and press the button.
Select "Self check" with the F1 or F2 button, and press the button.
1Select "Service" from the Main menu, and press the button.
3Check code, unit number, attribute will appear.
"-" will appear if no error history is available.
4Resetting the error history.
Press the F4 button (Reset) on the screen that shows the error history.
A confirmation screen will appear asking if you want to delete the error history.
Press the F4 button (OK) to delete the error history.
If deletion fails, "Request rejected" will appear.
"Unit not exist" will appear if no indoor units that are correspond to the entered
address are found.
Navigating through the screens
• To go back to the Service menu .......... button
• To return to the previous screen ....... button
10-3. HOW TO PROCEED "SELF-DIAGNOSIS"
10-3-1. Self-diagnosis <PAR-32MAA>
As this air conditioner has a function to memorize all the failures that had occured, the latest failure detail can be recalled by
following the procedure below.
Use this function when the check code is not displayed with wired remote controller or the remote controller at use is wireless
type.

20
TCH004
If operations cannot be completed with the remote controller, diagnose the remote controller with this function.
F1 F2 F3 F4
unemecivreS
rosruC :unemniaM
Maintenance password
Remote controller check
F1 F2 F3 F4
Remote controller check
:nigeB
Start checking?
Remote controller check
:nigeB
Start checking?
1Select "Service" from the Main menu, and press the button.
Select "Remote controller check" with the F1 or F2 button, and press
the button.
2
Select "Remote controller check" from the Service menu, and press the but-
ton to start the remote controller check and see the check results.
To cancel the remote controller check and exit the Remote controller check
menu screen, press the or the button.
The remote controller will not reboot itself.
Check the remote controller display and see if anything is displayed
(including lines). Nothing will appear on the remote controller display if
the correct voltage (8.5–2 V DC) is not supplied to the remote controller.
If this is the case, check the remote controller wiring and indoor units.
OK: No problems are found with the remote controller. Check other
parts for problems.
E3, 6832: There is noise on the transmission line, or the indoor unit or another
remote controller is faulty. Check the transmission line and the
other remote controllers.
NG (ALL0, ALL1):
Send-receive circuit fault. Remote controller needs replacing.
ERC: The number of data errors is the discrepancy between the number of
bits in the data transmitted from the remote controller and that of the
data that was actually transmitted over the transmission line. If data
errors are found, check the transmission line for external noise inter-
ference.
Remote controller check results screen
If the button is pressed after the remote controller check results are dis-
played, remote controller check will end, and the remote controller will automati-
cally reboot itself.
10-3-2. Remote controller check <PAR-32MAA>
3