Mitsubishi Electric MFZ-KA25VA User manual

CONTENTS
1. TECHNICAL CHANGES ··································· 2
2. PART NAMES AND FUNCTIONS····················· 3
3. SPECIFICATION················································ 5
4. NOISE CRITERIA CURVES······························ 7
5. OUTLINES AND DIMENSIONS ························ 8
6. WIRING DIAGRAM············································ 9
7. REFRIGERANT SYSTEM DIAGRAM············· 10
8. PERFORMANCE CURVES····························· 10
9. SERVICE FUNCTIONS ··································· 21
10. TROUBLESHOOTING····································· 23
11. DISASSEMBLY INSTRUCTIONS···················· 37
12. PARTS LIST····················································· 41
13. RoHS PARTS LIST·········································· 45
14. OPTIONAL PARTS·········································· 49
MFZ-KA25VA - E1 MFZ-KA50VA - E1
MFZ-KA25VA - E2 MFZ-KA50VA - E2
MFZ-KA25VA - E3 MFZ-KA50VA - E3
MFZ-KA25VA - E4 MFZ-KA50VA - E4
MFZ-KA35VA - E1
MFZ-KA35VA - E2
MFZ-KA35VA - E3
MFZ-KA35VA - E4
SPLIT-TYPE AIR CONDITIONERS
MFZ-KA25VA
MFZ-KA35VA
MFZ-KA50VA
NOTE:
• This service manual describes technical data of the indoor units.
• RoHS compliant products have <G> mark on the spec name plate.
For servicing of RoHS compliant products, refer to the RoHS Parts List.
SERVICE MANUAL
Models
No. OB409
REVISED EDITION-D
INDOOR UNIT
Revision D:
MFZ-KA25VA- E4 , MFZ-KA35VA- E4 and
MFZ-KA50VA- E4 have been added.
Outdoor unit service manual
SUZ-KA•VA(H) Series (OC322)
MXZ-A•VA Series (OB377, OC316)
Please void OB409 REVISED EDITION-C.

2
1TECHNICAL CHANGES
MFZ-KA25VA- E1 MFZ-KA25VA- E2
MFZ-KA35VA- E1 MFZ-KA35VA- E2
MFZ-KA50VA- E1 MFZ-KA50VA- E2
1. Operation of thermo-off-unit has been changed. (When 2 or more indoor units are connected with a multi type outdoor
unit, and operated in heat mode.)
< E1 > Indoor fan operates with very Low speed or stops.
< E2 > Indoor fan operates intermittently with very Low speed or stops.
MFZ-KA25VA- E2 MFZ-KA25VA- E3
MFZ-KA35VA- E2 MFZ-KA35VA- E3
MFZ-KA50VA- E2 MFZ-KA50VA- E3
1. Control of auto fan speed has been changed. (When indoor units are connected with a multi type outdoor
unit, and operated in heat mode.)
Air flow in auto fan speed is changed depending on air outlet temperature of indoor unit.
MFZ-KA25VA- E3 MFZ-KA25VA- E4
MFZ-KA35VA- E3 MFZ-KA35VA- E4
MFZ-KA50VA- E3 MFZ-KA50VA- E4
1. Fan motor has been changed.
Revision A:
• MFZ-KA25VA- E2 , MFZ-KA35VA- E2 and MFZ-KA50VA- E2 have been added.
• “Failure mode recall function” has been corrected.
• RoHS PARTS LIST has been added.
Revision B:
• MFZ-KA25VA- E3 , MFZ-KA35VA- E3 and MFZ-KA50VA- E3 have been added.
Revision C:
• Information for SUZ-KA25VA(H)R1.TH and SUZ-KA35VA(H)R1.TH has been added.
Revision D:
• MFZ-KA25VA- E4 , MFZ-KA35VA- E4 and MFZ-KA50VA- E4 have been added.

3
2PART NAMES AND FUNCTIONS
INDOOR UNIT
MFZ-KA25VA
MFZ-KA35VA
MFZ-KA50VA
Vertical vane
Air outlet
Horizontal vane
Catechin air filter
Display and operation section (When the front grille is opened)
Remote controller
Operation indicator lamp
Emergency operation switch
Air outlet selection switch
Remote control
receiving section
Front grille
Fan guard
Air cleaning filter
(Anti-Allergy Enzyme
Filter, blue bellows type)
Damper
Air outlet
Air inlet
Panel
Vertical vane

44
ACCESSORIES
REMOTE CONTROLLER
Drain hose
Remote controller holder
Fixing screw for 3.5 x 1.6 mm (Black)
Pipe cover
Band
Battery (AAA) for remote controller
Indoor unit mounting bracket
Fixing screw for 4 x 25 mm
Wood screw for the indoor unit fixation
Washer of
Felt tape (Used for left or left-rear piping)
Wireless remote controller
Air cleaning filter
MFZ-KA25VA
MFZ-KA35VA
1
1
2
1
2
2
1
5
4
4
1
1
1
MFZ-KA50VA
MFZ-KA25VA
MFZ-KA35VA
MFZ-KA50VA
(This diagram shows an overall view.)
.)
ra verall view.)
Open the front lid.
ON-TIMER button
CLOCK SET button
TIME SET buttons
FORWARD button
BACKWARD button
OFF-TIMER button
i save button
RESET button
VANE CONTROL button
FAN SPEED CONTROL button
OPERATION SELECT button
ECONO COOL button
Signal transmitting section
Operation display section
Temperature buttons
OPERATE/STOP
(ON/OFF) button
Indication of
remote controller
model is on back

5
3SPECIFICATION
Indoor model MFZ-KA25VA MFZ-KA35VA MFZ-KA50VA
Function Cooling Heating Cooling Heating Cooling Heating
Power supply Single phase
230 V, 50 Hz
Single phase
230 V, 50 Hz
Single phase
230 V, 50 Hz
Air flow (Super High) m3/h 522 546 546 570 642 708
Air flow (High/Med./Low) m3/h 426/348/288 456/372/300 444/366/300 468/372/312 552/474/426 588/528/444
Electrical
data
Breaker capacity A 10 10 10
Running current 1 A 0.2 0.2 0.2
Power input 1 W 25 25 25
Auxiliary heater A(kW) — — —
Power factor 1 % 54 54 54
Fan motor current 1 A 0.2 0.2 0.2
Fan
motor
Model (Upper) E1
,
E2
,
E3 RC0J30-GA RC0J30-GA RC0J30-GA
E4 RC0J30-KG RC0J30-KG RC0J30-KG
Model (Lower) E1
,
E2
,
E3 RC0J30-HA RC0J30-HA RC0J30-HA
E4 RC0J30-HB RC0J30-HB RC0J30-HB
Dimensions W x H x D mm 700 x 600 x 200 700 x 600 x 200 700 x 600 x 200
Weight kg 14 14 14
Special
remarks
Air direction 5 5 5
Sound level(Super High) dB(A) 37 38 43 44
Sound level(High/Med./Low) dB(A) 32/27/22 33/28/23 38/28/25 39/35/32
Upper
Fan speed(Super High) rpm 1,080 1,010 1,130 1,030 1,280 1,260
Fan speed(High/Med./Low) rpm 940/800/700 870/740/630 970/830/720 890/740/650 1,140/1,020/940 1,070/930/850
Lower
Fan speed(Super High) rpm 880 1,010 930 1,030 1,080 1,260
Fan speed(High/Med./Low) rpm 740/650/550 870/740/630 770/680/570 890/740/650 940/820/740 1,070/930/850
Fan speed regulator 4 4 4
Remote controller model KM05G KM05G KM05G
NOTE: Test conditions are based on ISO 5151.
Cooling: Indoor Dry-bulb temperature 27 Wet-bulb temperature 19
Outdoor Dry-bulb temperature 35 Wet-bulb temperature 24
Heating: Indoor Dry-bulb temperature 20 Wet-bulb temperature 15
Outdoor Dry-bulb temperature 7 Wet-bulb temperature 6
Refrigerant piping length (one way): 5 m
1 Measured under rated operating frequency.

6
T3.15AL 250 V
12 V 250 Ω
12 V 250 Ω
12 V 250 Ωor 12 V 300 Ω
12 V 300 Ω
ERZV14D471
Item Model
Fuse
Damper lock motor Right
Damper lock motor Left
Horizontal vane motor
Damper motor
Varistor
MFZ-KA25VA MFZ-KA35VA MFZ-KA50VA
(F11)
(ML1)
(ML2)
(MV1)
(MV2)
(NR11)
Specifications and rating conditions of main electric parts
Outdoor model
SUZ-KA25VA(H).TH
SUZ-KA25VA(H)R1.TH
Indoor model
MFZ-KA25VA
SUZ-KA35VA(H).TH
SUZ-KA35VA(H)R1.TH
Indoor model
MFZ-KA35VA
SUZ-KA50VA.TH
SUZ-KA50VA1.TH
Indoor model
MFZ-KA50VA
SUZ-KA50VAR2.TH
Indoor model
MFZ-KA50VA
Function Cooling Heating Cooling Heating Cooling Heating Cooling Heating
Power supply Single phase
230 V, 50 Hz
Single phase
230 V, 50 Hz
Single phase
230 V, 50 Hz
Single phase
230 V, 50 Hz
Capacity Rated frequency(Min.~Max.) kW 2.5 (0.9 - 3.4) 3.4 (0.9 - 5.1) 3.5 (0.9 - 3.9) 4.0 (0.9 - 6.2) 4.8 (0.9 - 5.4) 6.0(0.9 - 7.9) 4.8 (0.9 - 5.4) 6.0(0.9 - 7.9)
Dehumidification /h 1.2 1.7 2.5 2.5
Air flow(High/Low) m3/h
25VA(H).TH 35VA(H).TH
2,940/1,650 2,940/2,210 2,940/1,650 2,940/2,210
1,890/1,746 2,058/1,506 1,896/1,668 1,956/1,356
25VA(H)R1.TH 35VA(H)R1.TH
1,806/1,806 2,106/1,452 1,872/1,086 2,016/1,386
Electrical data
Starting current 1 A 4.0 5.0 8.5 8.5
Compressor motor current 1 A 2.3 3.5 4.5 4.5 6.5 8.0 6.5 8.0
Fan motor current 1 A 0.33 0.33 0.30 0.30
Coefficient of performance (C.O.P) 1 4.31 4.07 3.21 3.64 3.10 3.23 3.10 3.23
Compressor
Model
25VA(H).TH
KNB073FDVH
35VA(H).TH
KNB092FCAH SNB130FLDH or
SNB130FLDH1 SNB130FGBH
25VA(H)R1.TH
KNB073FFDHC
35VA(H)R1.TH
KNB092FFAHC
Output W 550 650 850 900
Winding
resistance(at 20 ºC) Ω
25VA(H).TH
U-V 1.53
UW 1.53
V-W 1.53
35VA(H).TH
U-V 0.49
U-W 0.49
V-W 0.49
U-V 0.45
U-W 0.45
V-W 0.45
U-V 0.45
U-W 0.45
V-W 0.45
25VA(H)R1.TH
U-V 1.70
U-W 1.70
V-W 1.70
35VA(H)R1.TH
U-V 1.91
U-W 1.91
V-W 1.91
Fan
motor
Model RC0J50-AL RC0J50-AL RC0J60-AA RC0J60-AA
Winding
resistance(at 20 ºC) Ω
WHT-BLK 37.5
BLK-RED 37.5
RED-WHT 37.5
WHT-BLK 37.5
BLK-RED 37.5
RED-WHT 37.5
WHT-BLK 15.2
BLK-RED 15.2
RED-WHT 15.2
WHT-BLK 15.2
BLK-RED 15.2
RED-WHT 15.2
Dimensions W x H x D mm 800 x 550 x 285 800 x 550 x 285 840 x 850 x 330 840 x 850 x 330
Weight kg
25VA(H).TH
33
35VA(H).TH
37 53 53
25VA(H)R1.TH
30
35VA(H)R1.TH
33
Special
remarks
Sound level 1 dB 46 47 48 53 55 53 55
Fan speed(High/Low, High/Med./Low) rpm
25VA(H).TH 35VA(H).TH
800/480 800/650 780/480 780/620
810/750 880/810/650 840/760 880/800/630
25VA(H)R1.TH 35VA(H)R1.TH
740/740 860/740/600 810/490 870/770/610
Fan speed regulator 2 3 2 3 2 2
Refrigerant filling
capacity (R410A) kg 0.90 1.05 1.60 1.60
Refrigerating oil (Model) cc
320 (NEO22) 320 (NEO22) FLDH: 450 (NEO22)
FLDH1: 600 (NEO22) 450 (NEO22)
NOTE: Test conditions are based on ISO 5151.
Cooling: Indoor Dry-bulb temperature 27 Wet-bulb temperature 19
Outdoor Dry-bulb temperature 35 Wet-bulb temperature 24
Heating: Indoor Dry-bulb temperature 20 Wet-bulb temperature 15
Outdoor Dry-bulb temperature 7 Wet-bulb temperature 6
Refrigerant piping length (one way): 5 m
1 Measured under rated operating frequency.

7
4NOISE CRITERIA CURVES
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
OCTAVE BAND SOUND PRESSURE LEVEL, dB re 0.0002 MICRO BAR
BAND CENTER FREQUENCIES, Hz
Test conditions,
Cooling : Dry-bulb temperature 27 °C Wet-bulb temperature 19 °C
COOLING
FUNCTION
43
44
SPL(dB(A)) LINE
Super High
FAN SPEED
HEATING
Heating : Dry-bulb temperature 20 °C Wet-bulb temperature 15 °C
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
OCTAVE BAND SOUND PRESSURE LEVEL, dB re 0.0002 MICRO BAR
BAND CENTER FREQUENCIES, Hz
Test conditions,
Cooling : Dry-bulb temperature 27 °C Wet-bulb temperature 19 °C
COOLING
FUNCTION
37
37
SPL(dB(A)) LINE
Super High
FAN SPEED
HEATING
Heating : Dry-bulb temperature 20 °C Wet-bulb temperature 15 °C 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
OCTAVE BAND SOUND PRESSURE LEVEL, dB re 0.0002 MICRO BAR
BAND CENTER FREQUENCIES, Hz
Test conditions,
Cooling : Dry-bulb temperature 27 °C Wet-bulb temperature 19 °C
COOLING
FUNCTION
38
38
SPL(dB(A)) LINE
Super High
FAN SPEED
HEATING
Heating : Dry-bulb temperature 20 °C Wet-bulb temperature 15 °C
NC-10
NC-10
NC-10
MFZ-KA25VA
INDOOR UNIT
WALL
1m 1m
MICROPHONE
MFZ-KA35VA
MFZ-KA50VA

8
Wireless remote controller
162
19
58
60
12
19 60
125
147
454155
60
35
45
110
80
60
72
337 337
363
333210
593
7
131131
4- 6 Hole
Indoor unit
Installation plate
96
123
125
6019
12
60
128
118
165
205
20012
12
11
Gas pipe
25, 35: 9.52(flared)3/8
50: 12.7(flared)1/2
Liquid pipe
6.35(flared)1/4
drain
Air in
Air out
Air out
46.5 46.5
600
700
54 508 137
607
More than 100mm
More than
100mm
More than
100mm
OUTLINES AND DIMENSIONS
5
Unit: mm
INDOOR UNIT
MFZ-KA25VA
MFZ-KA35VA
MFZ-KA50VA

9
6WIRING DIAGRAM
GRN
S1
1
2
CN202
12-24V
TB
S3 RED
BLK
TO OUTDOOR
UNIT
CONNECTING
INDOOR ELECTRONIC
CONTROL P.C. BOARD
WHT
230V~
S2 WHT CN201
1
2
LD103
3
3
CN112
CN113
111
RT11
RT15
5
3
1
2
4
6
CN
1
2
3
4
RT12
RT13
RT14
CN
1Y1
CN
1X1
LS1
LS2
CN212
T11
F11
NR11
DB111
ML1
MV1
55
CN
151
MF2
MF1
5
5
ML2
152
MV2
55
CN
106
CN CN
125
62
6
4
2
1
5
3
CN211
6
4
2
1
5
3
DISP REC
P.C.BOARD
MFZ-KA25VA- E1 ,E2
MFZ-KA35VA- E1 ,E2
MFZ-KA50VA- E1 ,E2
: Terminal block, : Connector
MFZ-KA25VA- E3 ,E4
MFZ-KA35VA- E3 ,E4
MFZ-KA50VA- E3 ,E4

10
PERFORMANCE CURVES
8
The standard data contained in these specifications apply only to the operation of the air conditioner under normal condition.
Operating conditions vary according to the areas where these units are installed. The following information has been provided
to clarify the operating characteristics of the air conditioner under the conditions indicated by the performance curve.
(1) GUARANTEED VOLTAGE
(2) AIR FLOW
Air flow should be set at MAX.
(3) MAIN READINGS
COOLING
(1) Indoor intake air wet-bulb temperature: W.B. ˚C
(2) Indoor outlet air wet-bulb temperature: W.B. ˚C
(3) Outdoor intake air dry-bulb temperature: D.B. ˚C
(4) Total input: W
Indoor air wet/dry-bulb temperature difference on the side of the following chart shows the difference between the
indoor intake air wet/dry-bulb temperature and the indoor outlet air wet/dry-bulb temperature for your reference at service.
How to measure the indoor air wet-bulb/dry-bulb temperature difference
1. Attach at least 2 sets of wet-and-dry-bulb thermometers to the indoor air inlet as shown in the figure, and at least 2 sets of
wet-and-dry-bulb thermometers to the indoor air outlet. The thermometers must be attached to the position where air speed
is high.
2. Attach at least 2 sets of wet-and-dry-bulb thermometers to the outdoor air inlet.
Cover the thermometers to prevent direct rays of the sun.
3. Check that the air filter is cleaned.
4. Open windows and doors of the room.
5. Press the EMERGENCY OPERATION switch once to start the COOL (HEAT) MODE.
6. When system stabilizes after more than 15 minutes, measure temperature and take an average temperature.
7. 10 minutes later, measure temperature again and check that the temperature does not change.
MFZ-KA25VA
MFZ-KA35VA
MFZ-KA50VA
REFRIGERANT SYSTEM DIAGRAM
7
Indoor
heat
exchanger
Flared connection
Room temperature
thermistor
RT11
Indoor coil
thermistor
RT12, RT14,
RT15 (main)
RT13 (sub)
Flared connection
Refrigerant flow in cooling
Refrigerant flow in heating
Refrigerant pipe 9.52 (MFZ-KA25/35VA)
Refrigerant pipe 12.7 (MFZ-KA50VA)
(with heat insulator)
Refrigerant pipe 6.35
(with heat insulator)
Indoor coil
thermistor
RT12 (main)
Distributor
INDOOR UNIT
Unit: mm
MFZ-KA25VA
MFZ-KA35VA
MFZ-KA50VA
HEATING
(1) Indoor intake air dry-bulb temperature: D.B. ˚C
(2) Indoor outlet air dry-bulb temperature: D.B. ˚C
(3) Outdoor intake air wet-bulb temperature: W.B. ˚C
(4) Total input: W