Mitsubishi Electric MUFZ-KJ25VEHZ User manual

SERVICE MANUAL
CONTENTS
1. TECHNICAL CHANGES ··································· 3
2. PART NAMES AND FUNCTIONS····················· 3
3. SPECIFICATION················································ 4
4. NOISE CRITERIA CURVES ······························ 6
5. OUTLINES AND DIMENSIONS ························ 7
6. WIRING DIAGRAM············································ 8
7. REFRIGERANT SYSTEM DIAGRAM ··············· 9
8. PERFORMANCE CURVES ····························· 10
9. ACTUATOR CONTROL··································· 19
10. SERVICE FUNCTIONS···································· 20
11. TROUBLESHOOTING ····································· 21
12. DISASSEMBLY INSTRUCTIONS···················· 39
Models
SPLIT-TYPE AIR CONDITIONERS
NOTE:
RoHS compliant products have <G> mark on the spec name plate.
HFC
utilized
R410A
No. OBH668
OUTDOOR UNIT
Indoor unit service manual
MFZ-KJ•VE Series (OBH666)
PARTS CATALOG (OBB668)
MUFZ-KJ25VEHZ -E1
MUFZ-KJ35VEHZ -E1

2
<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 and remove the power plug.
Discharge the capacitor 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 refrigeration 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 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.
OBH668

3
MUFZ-KJ25VEHZ - E1
MUFZ-KJ35VEHZ - E1
1. New model
TECHNICAL CHANGES
1
Air outlet
Drain outlet
Piping
Drain hose
Air inlet
(back and side)
MUFZ-KJ25VEHZ
MUFZ-KJ35VEHZ
PART NAMES AND FUNCTIONS
2
OBH668

4
Outdoor model MUFZ-KJ25VEHZ MUFZ-KJ35VEHZ
Power supply Single phase, 230 V, 50 Hz
Capacity
Rated frequency (Min.-Max.)
Cooling kW 2.5 (0.5 - 3.4) 3.5 (0.5 - 3.7)
Heating 3.4 (1.2 - 5.1) 4.3 (1.2 - 5.8)
Breaker Capacity A 10 12
Electrical data
Power input 1 (Total) Cooling W540 940
Heating 770 1,110
Running current 1
(Total)
Cooling A2.7 4.2
Heating 3.6 5.1
Power factor 1 (Total) Cooling %87 98
Heating 91 93
Starting current 1 (Total) A 3.6 5.1
Coefficient of performance
(COP) 1 (Total)
Cooling 4.63 3.72
Heating 4.42 3.91
Compressor
Model SNB140FRUMT
Output W 950
Current 1 Cooling A2.19 3.69
Heating 3.16 4.61
Refrigeration oil (Model) L 0.35 (FV50S)
Fan motor
Model RC0J50-CI
Current 1Cooling A0.31
Heating 0.31
Dimensions W × H × D mm 800 × 550 × 285
Weight kg 37
Special remarks
Dehumidification Cooling L/h 0.6 1.4
Air flow 1
Cooling Med.
m3/h
1,806
Low 1,038
Heating
High 2,016
Med. 1,710
Low 1,326
Sound
level 1
Cooling dB(A) 46 47
Heating 51
Fan speed
Cooling Med.
rpm
810
Low 490
Heating
High 900
Med. 770
Low 610
Fan speed regulator 3
Refrigerant filling capacity (R410A) kg 1.10
NOTE: Test conditions are based on ISO 5151.
Cooling: Indoor Dry-bulb temperature 27°C Wet-bulb temperature 19°C
Outdoor Dry-bulb temperature 35°C
Heating: Indoor Dry-bulb temperature 20°C
Outdoor Dry-bulb temperature 7°C Wet-bulb temperature 6°C
Refrigerant piping length (one way): 5 m
1 Measured under rated operating frequency.
SPECIFICATION
3
OBH668

5
Specifications and rated conditions of main electric parts
Model
Item MUFZ-KJ25VEHZ MUFZ-KJ35VEHZ
Smoothing
capacitor (C61, C62) 600 μF/ 620 μF 420 V
Diode module (DB61) 15 A 600 V
Fuse (F61) T20AL250V
(F701, F801, F901) T3.15AL250V
Defrost heater (H) 230 V 130 W
Power module (IC700) 15 A 600 V
(IC932) 8A600V
Expansion valve
coil (LEV) 12 V DC
Reactor (L61) 23 mH
Power factor
controller (IC820) 20A 600V
Circuit
protection (PTC64, PTC65) 33 Ω
Terminal block (TB) 5 P
Relay
(X63) 3 A 250 V
(X64) 20 A 250 V
(X66) 3 A 250 V
(X69) 10A 250V
R.V. coil (21S4) 220 - 240 V AC
Heater protector (26H) Open 45°C
OBH668

6
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, 0dB re 0.0002 MICRO BAR
BAND CENTER FREQUENCIES, Hz
COOLING
FUNCTION SPL(dB(A)) LINE
HEATING
46
51
NC-10
MUFZ-KJ25VEHZ
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
COOLING
FUNCTION SPL(dB(A)) LINE
HEATING
47
51
NC-10
MUFZ-KJ35VEHZ
NOISE CRITERIA CURVES
4
Test conditions
Cooling: Dry-bulb temperature 35°C
Heating: Dry-bulb temperature 7°C Wet-bulb temperature 6°C
OUTDOOR UNIT
MICROPHONE
1 m
OBH668

7
Unit: mm
MUFZ-KJ25VEHZ
MUFZ-KJ35VEHZ
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) ø6.35
Gas refrigerant pipe joint
Refrigerant pipe (flared) ø9.52
43
35
2 holes 10 X 21
REQUIRED SPACE
100 mm or more
350 mm or more
200 mm or more
100 mm or more
100 mm or more
Drain hole ø33
OUTLINES AND DIMENSIONS
5
OBH668

8
WIRING DIAGRAM
6
MUFZ-KJ25VEHZ
MUFZ-KJ35VEHZ
OBH668

9
Unit: mm
MUFZ-KJ25VEHZ
MUFZ-KJ35VEHZ
Outdoor
heat
exchanger
Flared connection
Defrost
thermistor
RT61
Discharge
temperature
thermistor
RT62
Flared connection
Stop valve
(with strainar)
Stop valve
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
LEV
Ambient
temperature
thermistor
RT65
Muffler
Capillary tube
ø4.0×ø2.4×240
Outdoor heat
exchanger
temperature
thermistor
RT68
Capillary tube
ø3.0×ø2.0×210
Muffler
REFRIGERANT SYSTEM DIAGRAM
7
Max. Length
A
Max. Height
difference
B
Indoor
unit
Outdoor unit
MAX. REFRIGERANT PIPING LENGTH and MAX. HEIGHT DIFFERENCE
Model Refrigerant piping: m Piping size O.D: mm
Max. Length A Max. Height difference B Gas Liquid
MUFZ-KJ25/35 20 12 9.52 6.35
ADDITIONAL REFRIGERANT CHARGE (R410A: g)
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
MUFZ-KJ25/35 1,100 0 30 60 90 120 150 180 210 240 390
Calculation: X g = 30 g/m × (Refrigerant piping length (m) - 7)
OBH668

10
The standard specifications apply only to the operation of the air conditioner under normal conditions. Since operating condi-
tions 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
198 ~ 264 V, 50 Hz
(2) AIR FLOW
Air flow should be set at MAX.
(3) MAIN READINGS
(1) Indoor intake air wet-bulb temperature: °C [WB]
}
Cooling
(2) Indoor outlet air wet-bulb temperature: °C [WB]
(3) Outdoor intake air dry-bulb temperature: °C [DB]
(4) Total input: W
(5) Indoor intake air dry-bulb temperature: °C [DB]
}
Heating(6) Outdoor intake air wet-bulb temperature: °C [WB]
(7) Total input: W
Indoor air wet and dry bulb temperature difference on the left side of the following chart shows the difference between the
indoor intake air wet and dry bulb temperature and the indoor outlet air wet and dry bulb temperature for your reference at
service.
How to measure the indoor air wet and dry bulb temperature difference
1. Attach at least 2 sets of wet and dry bulb thermometers to the indoor air intake 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 intake.
Cover the thermometers to prevent direct rays of the sun.
3. Check that the air filter is cleaned.
4. Open windows and doors of room.
5. Press the EMERGENCY OPERATION switch once (twice) to start the EMERGENCY 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.
MUFZ-KJ25VEHZ
MUFZ-KJ35VEHZ
INDOOR UNIT OUTDOOR UNIT
Wet and dry bulb
thermometers
FRONT VIEW
Wet and dry bulb
thermometers
BACK VIEW
Cooling capacity ( at Rated frequency)
0.9
1.0
1.1
1.2
1.3
1.4
1.5
-10-5 0 5 1015202530354045
Outdoor intake air Dry-bulb temperature(°C)
Capacity correction factors
26
24
20
18
22
Indoor intake air Wet-bulb
temperature( )
MUFZ-KJ35VEHZ
MUFZ-KJ25VEHZ
Indoor air Wet-bulb temperature
difference (°C)
8.5
7.9
7.2
6.6
6.0
5.4
4.8
12.9
11.8
10.8
9.8
8.8
7.9
7.0
8-1. CAPACITY AND INPUT CURVES
PERFORMANCE CURVES8
OBH668

11
NOTE: The above broken lines are for the heating operation without any frost and defrost operation.
0.8
0.9
1.0
1.1
1.2
1.3
-10-5 0 5 1015202530354045
Outdoor intake air Dry-bulb temperature (°C)
Input correction factors
26 24 22
20
18
Indoor intake air Wet-bulb
temperature( )
Indoor air Wet-bulb temperature
difference (°C)
7.2
6.6
6.0
5.4
4.8
4.2
10.8
9.8
8.8
7.9
7.0
6.1
MUFZ-KJ35VEHZ MUFZ-KJ25VEHZ
Total input (Cooling : at Rated frequency )
Indoor air Dry-bulb temperature
difference (°C)
22.9
21.2
19.4
17.6
15.9
14.1
12.3
10.6
8.8
7.1
MUFZ-KJ25VEHZ
29.0
26.8
24.5
22.3
20.1
17.8
15.6
13.4
11.1
8.9
MUFZ-KJ35VEHZ
Outdoor intake air Wet-bulb temperature (°C)
-20 -15 -10 -5 0 5 10 15
0.4
0.5
0.6
0.7
0.8
0.9
1.0
1.1
1.2
1.3
Heating capacity ( at Rated frequency)
Capacity correction factor
15
20
26
Indoor intake air Dry-bulb temperature ( )
Indoor air Dry-bulb temperature
difference (°C)
22.9
21.2
19.4
17.6
15.9
14.1
12.3
10.6
8.8
7.1
MUFZ-KJ25VEHZ
29.0
26.8
24.5
22.3
20.1
17.8
15.6
13.4
11.1
8.9
MUFZ-KJ35VEHZ
Outdoor intake air Wet-bulb temperature (°C)
-20 -15 -10 -5 0 5 10 15
0.4
0.5
0.6
0.7
0.8
0.9
1.0
1.1
1.2
1.3
Total input (Heating : at Rated frequency )
Input correction factor
15
20
26
Indoor intake air Dry-bulb temperature ( )
OBH668

12
8-2. CAPACITY AND INPUT CORRECTION BY OPERATIONAL FREQUENCY OF COMPRESSOR
0 50 100
0.5
1.0
1.5
0 50 100
0.5
1.0
1.5
0 50 100
0.5
1.0
1.5
2.0
0 50 100
0.5
1.0
1.5
2.0
0 50 100 150
0.5
1.0
1.5
2.0
050100
150
1
2
3
0 50 100 150
0.5
1.0
1.5
050100
150
1
2
3
MUFZ-KJ25VEHZ
MUFZ-KJ35VEHZ
Correction of Cooling capacity
The operational frequency
of compressor (Hz)
Capacity correction factors
Correction of Cooling input
The operational f requency
of compressor (Hz)
Input correction factors
Correction of Heating capacity
The operational f requency
of compressor (Hz)
Capacity correction factors
Correction of Heating input
The operational f requency
of compressor (Hz)
Input correction factors
Correction of Cooling capacity
The operational frequency
of compressor (Hz)
Capacity correction factors
Correction of Cooling input
Input correction factors
Correction of Heating capacity
The operational frequency
of compressor (Hz)
Capacity correction factors
Correction of Heating input
The operational f requency
of compressor (Hz)
Input correction factors
The operational frequency
of compressor (Hz)
8-3. HOW TO OPERATE FIXED-FREQUENCY OPERATION
<Test run operation>
1. Press EMERGENCY OPERATION switch to start COOL or HEAT mode (COOL: Press once, HEAT: Press twice).
2. Test run operation starts and continues to operate for 30 minutes.
3. Compressor operates at rated frequency in COOL mode or 58 Hz in HEAT mode.
4. Indoor fan operates at High speed.
5.
After 30 minutes, test run operation finishes and EMERGENCY OPERATION starts (operation frequency of compressor varies).
6. To cancel test run operation (EMERGENCY OPERATION), press EMERGENCY OPERATION switch or any button on
remote controller.
OBH668

13
15 20 25 30 35
0.4
0.5
0.6
0.7
0.8
0.9
15 20 25 30 35
0.4
0.5
0.6
0.7
0.8
(kgf/cm2[Gauge])(MPa [Gauge])
6
5
4
7
8
9
(kgf/cm2[Gauge])(MPa [Gauge])
4
6
5
7
8
50 60 70
Ambient temperature(°C)
Ambient humidity(%)
50 60 70
Ambient temperature(°C)
Ambient humidity(%)
Outdoor low pressure
MUFZ-KJ25VEHZ MUFZ-KJ35VEHZ
COOL operation
Both indoor and outdoor unit are under the same temperature/
humidity condition.
Operation: TEST RUN OPERATION (Refer to 8-3.)
8-4. OUTDOOR LOW PRESSURE AND OUTDOOR UNIT CURRENT
Dry-bulb temperature (°C) Relative humidity (%)
20 50
25 60
30 70
NOTE:
The unit of pressure has been changed to MPa on the international system of units (SI unit system)
The conversion factor is: 1 (MPa [Gauge]) = 10.2 (kgf/cm2[Gauge])
15 20 25 30 35
1.5
2.0
2.5
3.0
15 20 25 30 35
2.5
3.0
3.5
4.0
4.5
Ambient temperature (°C)
Ambient humidity(%)
50 60 70 50 60 70
Outdoor current (A)
Ambient temperature (°C)
Ambient humidity(%)
Outdoor current (A)
MUFZ-KJ35VEHZMUFZ-KJ25VEHZ
Outdoor unit current
0510
15 20 25
2.5
3.0
3.5
4.0
4.5
0510
15 20 25
4.0
4.5
5.0
5.5
6.0
Ambient temperature (°C)
Outdoor current (A)
Ambient temperature (°C)
Outdoor current (A)
MUFZ-KJ35VEHZMUFZ-KJ25VEHZ
Outdoor unit current
Condition:
Operation: Test run operation (Refer to 8-3.)
HEAT operation
Indoor Outdoor
Dry bulb temperature (°C) 20.0 2 7 15 20.0
Wet bulb temperature (°C) 14.5 1 6 12 14.5
OBH668

14
PERFORMANCE DATA COOL operation at Rated frequency
MUFZ-KJ25VEHZ
CAPACITY: 2.5 kW SHF: 0.85 INPUT: 540 W
INDOOR
DB (°C)
INDOOR
WB (°C)
OUTDOOR DB (°C)
21 25 27 30
Q SHC SHF INPUT Q SHC SHF INPUT Q SHC SHF INPUT Q SHC SHF INPUT
21 18 2.94 1.97 0.67 432 2.81 1.88 0.67 454 2.70 1.81 0.67 475 2.60 1.74 0.67 497
21 20 3.06 1.68 0.55 454 2.94 1.62 0.55 481 2.85 1.57 0.55 491 2.75 1.51 0.55 513
22 18 2.94 2.09 0.71 432 2.81 2.00 0.71 454 2.70 1.92 0.71 475 2.60 1.85 0.71 497
22 20 3.06 1.81 0.59 454 2.94 1.73 0.59 481 2.85 1.68 0.59 491 2.75 1.62 0.59 513
22 22 3.19 1.50 0.47 470 3.08 1.45 0.47 500 3.00 1.41 0.47 513 2.88 1.35 0.47 535
23 18 2.94 2.20 0.75 432 2.81 2.11 0.75 454 2.70 2.03 0.75 475 2.60 1.95 0.75 497
23 20 3.06 1.93 0.63 454 2.94 1.85 0.63 481 2.85 1.80 0.63 491 2.75 1.73 0.63 513
23 22 3.19 1.63 0.51 470 3.08 1.57 0.51 500 3.00 1.53 0.51 513 2.88 1.47 0.51 535
24 18 2.94 2.32 0.79 432 2.81 2.22 0.79 454 2.70 2.13 0.79 475 2.60 2.05 0.79 497
24 20 3.06 2.05 0.67 454 2.94 1.97 0.67 481 2.85 1.91 0.67 491 2.75 1.84 0.67 513
24 22 3.19 1.75 0.55 470 3.08 1.69 0.55 500 3.00 1.65 0.55 513 2.88 1.58 0.55 535
24 24 3.35 1.44 0.43 491 3.23 1.39 0.43 518 3.15 1.35 0.43 535 3.05 1.31 0.43 562
25 18 2.94 2.44 0.83 432 2.81 2.33 0.83 454 2.70 2.24 0.83 475 2.60 2.16 0.83 497
25 20 3.06 2.17 0.71 454 2.94 2.09 0.71 481 2.85 2.02 0.71 491 2.75 1.95 0.71 513
25 22 3.19 1.88 0.59 470 3.08 1.81 0.59 500 3.00 1.77 0.59 513 2.88 1.70 0.59 535
25 24 3.35 1.57 0.47 491 3.23 1.52 0.47 518 3.15 1.48 0.47 535 3.05 1.43 0.47 562
26 18 2.94 2.56 0.87 432 2.81 2.45 0.87 454 2.70 2.35 0.87 475 2.60 2.26 0.87 497
26 20 3.06 2.30 0.75 454 2.94 2.20 0.75 481 2.85 2.14 0.75 491 2.75 2.06 0.75 513
26 22 3.19 2.01 0.63 470 3.08 1.94 0.63 500 3.00 1.89 0.63 513 2.88 1.81 0.63 535
26 24 3.35 1.71 0.51 491 3.23 1.64 0.51 518 3.15 1.61 0.51 535 3.05 1.56 0.51 562
26 26 3.45 1.35 0.39 518 3.35 1.31 0.39 545 3.30 1.29 0.39 562 3.20 1.25 0.39 578
27 18 2.94 2.67 0.91 432 2.81 2.56 0.91 454 2.70 2.46 0.91 475 2.60 2.37 0.91 497
27 20 3.06 2.42 0.79 454 2.94 2.32 0.79 481 2.85 2.25 0.79 491 2.75 2.17 0.79 513
27 22 3.19 2.14 0.67 470 3.08 2.06 0.67 500 3.00 2.01 0.67 513 2.88 1.93 0.67 535
27 24 3.35 1.84 0.55 491 3.23 1.77 0.55 518 3.15 1.73 0.55 535 3.05 1.68 0.55 562
27 26 3.45 1.48 0.43 518 3.35 1.44 0.43 545 3.30 1.42 0.43 562 3.20 1.38 0.43 578
28 18 2.94 2.79 0.95 432 2.81 2.67 0.95 454 2.70 2.57 0.95 475 2.60 2.47 0.95 497
28 20 3.06 2.54 0.83 454 2.94 2.44 0.83 481 2.85 2.37 0.83 491 2.75 2.28 0.83 513
28 22 3.19 2.26 0.71 470 3.08 2.18 0.71 500 3.00 2.13 0.71 513 2.88 2.04 0.71 535
28 24 3.35 1.98 0.59 491 3.23 1.90 0.59 518 3.15 1.86 0.59 535 3.05 1.80 0.59 562
28 26 3.45 1.62 0.47 518 3.35 1.57 0.47 545 3.30 1.55 0.47 562 3.20 1.50 0.47 578
29 18 2.94 2.91 0.99 432 2.81 2.78 0.99 454 2.70 2.67 0.99 475 2.60 2.57 0.99 497
29 20 3.06 2.66 0.87 454 2.94 2.56 0.87 481 2.85 2.48 0.87 491 2.75 2.39 0.87 513
29 22 3.19 2.39 0.75 470 3.08 2.31 0.75 500 3.00 2.25 0.75 513 2.88 2.16 0.75 535
29 24 3.35 2.11 0.63 491 3.23 2.03 0.63 518 3.15 1.98 0.63 535 3.05 1.92 0.63 562
29 26 3.45 1.76 0.51 518 3.35 1.71 0.51 545 3.30 1.68 0.51 562 3.20 1.63 0.51 578
30 18 2.94 2.94 1.00 432 2.81 2.81 1.00 454 2.70 2.70 1.00 475 2.60 2.60 1.00 497
30 20 3.06 2.79 0.91 454 2.94 2.67 0.91 481 2.85 2.59 0.91 491 2.75 2.50 0.91 513
30 22 3.19 2.52 0.79 470 3.08 2.43 0.79 500 3.00 2.37 0.79 513 2.88 2.27 0.79 535
30 24 3.35 2.24 0.67 491 3.23 2.16 0.67 518 3.15 2.11 0.67 535 3.05 2.04 0.67 562
30 26 3.45 1.90 0.55 518 3.35 1.84 0.55 545 3.30 1.82 0.55 562 3.20 1.76 0.55 578
31 18 2.94 2.94 1.00 432 2.81 2.81 1.00 454 2.70 2.70 1.00 475 2.60 2.60 1.00 497
31 20 3.06 2.91 0.95 454 2.94 2.79 0.95 481 2.85 2.71 0.95 491 2.75 2.61 0.95 513
31 22 3.19 2.65 0.83 470 3.08 2.55 0.83 500 3.00 2.49 0.83 513 2.88 2.39 0.83 535
31 24 3.35 2.38 0.71 491 3.23 2.29 0.71 518 3.15 2.24 0.71 535 3.05 2.17 0.71 562
31 26 3.45 2.04 0.59 518 3.35 1.98 0.59 545 3.30 1.95 0.59 562 3.20 1.89 0.59 578
32 18 2.94 2.94 1.00 432 2.81 2.81 1.00 454 2.70 2.70 1.00 475 2.60 2.60 1.00 497
32 20 3.06 3.03 0.99 454 2.94 2.91 0.99 481 2.85 2.82 0.99 491 2.75 2.72 0.99 513
32 22 3.19 2.77 0.87 470 3.08 2.68 0.87 500 3.00 2.61 0.87 513 2.88 2.50 0.87 535
32 24 3.35 2.51 0.75 491 3.23 2.42 0.75 518 3.15 2.36 0.75 535 3.05 2.29 0.75 562
32 26 3.45 2.17 0.63 518 3.35 2.11 0.63 545 3.30 2.08 0.63 562 3.20 2.02 0.63 578
NOTE Q : Total capacity (kW) SHF : Sensible heat factor DB : Dry-bulb temperature
SHC : Sensible heat capacity (kW) INPUT : Total power input (W) WB : Wet-bulb temperature
OBH668

15
PERFORMANCE DATA COOL operation at Rated frequency
MUFZ-KJ25VEHZ
CAPACITY: 2.5 kW SHF: 0.85 INPUT: 540 W
INDOOR
DB (°C)
INDOOR
WB (°C)
OUTDOOR DB (°C)
35 40 46
Q SHC SHF INPUT Q SHC SHF INPUT Q SHC SHF INPUT
21 18 2.45 1.64 0.67 529 2.25 1.51 0.67 562 2.08 1.39 0.67 583
21 20 2.58 1.42 0.55 551 2.40 1.32 0.55 578 2.23 1.22 0.55 610
22 18 2.45 1.74 0.71 529 2.25 1.60 0.71 562 2.08 1.47 0.71 583
22 20 2.58 1.52 0.59 551 2.40 1.42 0.59 578 2.23 1.31 0.59 610
22 22 2.73 1.28 0.47 572 2.55 1.20 0.47 605 2.38 1.12 0.47 626
23 18 2.45 1.84 0.75 529 2.25 1.69 0.75 562 2.08 1.56 0.75 583
23 20 2.58 1.62 0.63 551 2.40 1.51 0.63 578 2.23 1.40 0.63 610
23 22 2.73 1.39 0.51 572 2.55 1.30 0.51 605 2.38 1.21 0.51 626
24 18 2.45 1.94 0.79 529 2.25 1.78 0.79 562 2.08 1.64 0.79 583
24 20 2.58 1.73 0.67 551 2.40 1.61 0.67 578 2.23 1.49 0.67 610
24 22 2.73 1.50 0.55 572 2.55 1.40 0.55 605 2.38 1.31 0.55 626
24 24 2.88 1.24 0.43 594 2.70 1.16 0.43 621 2.55 1.10 0.43 648
25 18 2.45 2.03 0.83 529 2.25 1.87 0.83 562 2.08 1.72 0.83 583
25 20 2.58 1.83 0.71 551 2.40 1.70 0.71 578 2.23 1.58 0.71 610
25 22 2.73 1.61 0.59 572 2.55 1.50 0.59 605 2.38 1.40 0.59 626
25 24 2.88 1.35 0.47 594 2.70 1.27 0.47 621 2.55 1.20 0.47 648
26 18 2.45 2.13 0.87 529 2.25 1.96 0.87 562 2.08 1.81 0.87 583
26 20 2.58 1.93 0.75 551 2.40 1.80 0.75 578 2.23 1.67 0.75 610
26 22 2.73 1.72 0.63 572 2.55 1.61 0.63 605 2.38 1.50 0.63 626
26 24 2.88 1.47 0.51 594 2.70 1.38 0.51 621 2.55 1.30 0.51 648
26 26 3.03 1.18 0.39 616 2.85 1.11 0.39 643 2.68 1.04 0.39 670
27 18 2.45 2.23 0.91 529 2.25 2.05 0.91 562 2.08 1.89 0.91 583
27 20 2.58 2.03 0.79 551 2.40 1.90 0.79 578 2.23 1.76 0.79 610
27 22 2.73 1.83 0.67 572 2.55 1.71 0.67 605 2.38 1.59 0.67 626
27 24 2.88 1.58 0.55 594 2.70 1.49 0.55 621 2.55 1.40 0.55 648
27 26 3.03 1.30 0.43 616 2.85 1.23 0.43 643 2.68 1.15 0.43 670
28 18 2.45 2.33 0.95 529 2.25 2.14 0.95 562 2.08 1.97 0.95 583
28 20 2.58 2.14 0.83 551 2.40 1.99 0.83 578 2.23 1.85 0.83 610
28 22 2.73 1.93 0.71 572 2.55 1.81 0.71 605 2.38 1.69 0.71 626
28 24 2.88 1.70 0.59 594 2.70 1.59 0.59 621 2.55 1.50 0.59 648
28 26 3.03 1.42 0.47 616 2.85 1.34 0.47 643 2.68 1.26 0.47 670
29 18 2.45 2.43 0.99 529 2.25 2.23 0.99 562 2.08 2.05 0.99 583
29 20 2.58 2.24 0.87 551 2.40 2.09 0.87 578 2.23 1.94 0.87 610
29 22 2.73 2.04 0.75 572 2.55 1.91 0.75 605 2.38 1.78 0.75 626
29 24 2.88 1.81 0.63 594 2.70 1.70 0.63 621 2.55 1.61 0.63 648
29 26 3.03 1.54 0.51 616 2.85 1.45 0.51 643 2.68 1.36 0.51 670
30 18 2.45 2.45 1.00 529 2.25 2.25 1.00 562 2.08 2.08 1.00 583
30 20 2.58 2.34 0.91 551 2.40 2.18 0.91 578 2.23 2.02 0.91 610
30 22 2.73 2.15 0.79 572 2.55 2.01 0.79 605 2.38 1.88 0.79 626
30 24 2.88 1.93 0.67 594 2.70 1.81 0.67 621 2.55 1.71 0.67 648
30 26 3.03 1.66 0.55 616 2.85 1.57 0.55 643 2.68 1.47 0.55 670
31 18 2.45 2.45 1.00 529 2.25 2.25 1.00 562 2.08 2.08 1.00 583
31 20 2.58 2.45 0.95 551 2.40 2.28 0.95 578 2.23 2.11 0.95 610
31 22 2.73 2.26 0.83 572 2.55 2.12 0.83 605 2.38 1.97 0.83 626
31 24 2.88 2.04 0.71 594 2.70 1.92 0.71 621 2.55 1.81 0.71 648
31 26 3.03 1.78 0.59 616 2.85 1.68 0.59 643 2.68 1.58 0.59 670
32 18 2.45 2.45 1.00 529 2.25 2.25 1.00 562 2.08 2.08 1.00 583
32 20 2.58 2.55 0.99 551 2.40 2.38 0.99 578 2.23 2.20 0.99 610
32 22 2.73 2.37 0.87 572 2.55 2.22 0.87 605 2.38 2.07 0.87 626
32 24 2.88 2.16 0.75 594 2.70 2.03 0.75 621 2.55 1.91 0.75 648
32 26 3.03 1.91 0.63 616 2.85 1.80 0.63 643 2.68 1.69 0.63 670
NOTE Q : Total capacity (kW) SHF : Sensible heat factor DB : Dry-bulb temperature
SHC : Sensible heat capacity (kW) INPUT : Total power input (W) WB : Wet-bulb temperature
OBH668

16
PERFORMANCE DATA COOL operation at Rated frequency
MUFZ-KJ35VEHZ
CAPACITY: 3.5 kW SHF: 0.73 INPUT: 940 W
INDOOR
DB (°C)
INDOOR
WB (°C)
OUTDOOR DB (°C)
21 25 27 30
Q SHC SHF INPUT Q SHC SHF INPUT Q SHC SHF INPUT Q SHC SHF INPUT
21 18 4.11 2.26 0.55 752 3.94 2.17 0.55 790 3.78 2.08 0.55 827 3.64 2.00 0.55 865
21 20 4.29 1.84 0.43 790 4.11 1.77 0.43 837 3.99 1.72 0.43 855 3.85 1.66 0.43 893
22 18 4.11 2.43 0.59 752 3.94 2.32 0.59 790 3.78 2.23 0.59 827 3.64 2.15 0.59 865
22 20 4.29 2.02 0.47 790 4.11 1.93 0.47 837 3.99 1.88 0.47 855 3.85 1.81 0.47 893
22 22 4.46 1.56 0.35 818 4.31 1.51 0.35 870 4.20 1.47 0.35 893 4.03 1.41 0.35 931
23 18 4.11 2.59 0.63 752 3.94 2.48 0.63 790 3.78 2.38 0.63 827 3.64 2.29 0.63 865
23 20 4.29 2.19 0.51 790 4.11 2.10 0.51 837 3.99 2.03 0.51 855 3.85 1.96 0.51 893
23 22 4.46 1.74 0.39 818 4.31 1.68 0.39 870 4.20 1.64 0.39 893 4.03 1.57 0.39 931
24 18 4.11 2.76 0.67 752 3.94 2.64 0.67 790 3.78 2.53 0.67 827 3.64 2.44 0.67 865
24 20 4.29 2.36 0.55 790 4.11 2.26 0.55 837 3.99 2.19 0.55 855 3.85 2.12 0.55 893
24 22 4.46 1.92 0.43 818 4.31 1.85 0.43 870 4.20 1.81 0.43 893 4.03 1.73 0.43 931
24 24 4.69 1.45 0.31 855 4.52 1.40 0.31 902 4.41 1.37 0.31 931 4.27 1.32 0.31 978
25 18 4.11 2.92 0.71 752 3.94 2.80 0.71 790 3.78 2.68 0.71 827 3.64 2.58 0.71 865
25 20 4.29 2.53 0.59 790 4.11 2.43 0.59 837 3.99 2.35 0.59 855 3.85 2.27 0.59 893
25 22 4.46 2.10 0.47 818 4.31 2.02 0.47 870 4.20 1.97 0.47 893 4.03 1.89 0.47 931
25 24 4.69 1.64 0.35 855 4.52 1.58 0.35 902 4.41 1.54 0.35 931 4.27 1.49 0.35 978
26 18 4.11 3.08 0.75 752 3.94 2.95 0.75 790 3.78 2.84 0.75 827 3.64 2.73 0.75 865
26 20 4.29 2.70 0.63 790 4.11 2.59 0.63 837 3.99 2.51 0.63 855 3.85 2.43 0.63 893
26 22 4.46 2.28 0.51 818 4.31 2.20 0.51 870 4.20 2.14 0.51 893 4.03 2.05 0.51 931
26 24 4.69 1.83 0.39 855 4.52 1.76 0.39 902 4.41 1.72 0.39 931 4.27 1.67 0.39 978
26 26 4.83 1.30 0.27 902 4.69 1.27 0.27 949 4.62 1.25 0.27 978 4.48 1.21 0.27 1006
27 18 4.11 3.25 0.79 752 3.94 3.11 0.79 790 3.78 2.99 0.79 827 3.64 2.88 0.79 865
27 20 4.29 2.87 0.67 790 4.11 2.76 0.67 837 3.99 2.67 0.67 855 3.85 2.58 0.67 893
27 22 4.46 2.45 0.55 818 4.31 2.37 0.55 870 4.20 2.31 0.55 893 4.03 2.21 0.55 931
27 24 4.69 2.02 0.43 855 4.52 1.94 0.43 902 4.41 1.90 0.43 931 4.27 1.84 0.43 978
27 26 4.83 1.50 0.31 902 4.69 1.45 0.31 949 4.62 1.43 0.31 978 4.48 1.39 0.31 1006
28 18 4.11 3.41 0.83 752 3.94 3.27 0.83 790 3.78 3.14 0.83 827 3.64 3.02 0.83 865
28 20 4.29 3.04 0.71 790 4.11 2.92 0.71 837 3.99 2.83 0.71 855 3.85 2.73 0.71 893
28 22 4.46 2.63 0.59 818 4.31 2.54 0.59 870 4.20 2.48 0.59 893 4.03 2.37 0.59 931
28 24 4.69 2.20 0.47 855 4.52 2.12 0.47 902 4.41 2.07 0.47 931 4.27 2.01 0.47 978
28 26 4.83 1.69 0.35 902 4.69 1.64 0.35 949 4.62 1.62 0.35 978 4.48 1.57 0.35 1006
29 18 4.11 3.58 0.87 752 3.94 3.43 0.87 790 3.78 3.29 0.87 827 3.64 3.17 0.87 865
29 20 4.29 3.22 0.75 790 4.11 3.08 0.75 837 3.99 2.99 0.75 855 3.85 2.89 0.75 893
29 22 4.46 2.81 0.63 818 4.31 2.71 0.63 870 4.20 2.65 0.63 893 4.03 2.54 0.63 931
29 24 4.69 2.39 0.51 855 4.52 2.30 0.51 902 4.41 2.25 0.51 931 4.27 2.18 0.51 978
29 26 4.83 1.88 0.39 902 4.69 1.83 0.39 949 4.62 1.80 0.39 978 4.48 1.75 0.39 1006
30 18 4.11 3.74 0.91 752 3.94 3.58 0.91 790 3.78 3.44 0.91 827 3.64 3.31 0.91 865
30 20 4.29 3.39 0.79 790 4.11 3.25 0.79 837 3.99 3.15 0.79 855 3.85 3.04 0.79 893
30 22 4.46 2.99 0.67 818 4.31 2.88 0.67 870 4.20 2.81 0.67 893 4.03 2.70 0.67 931
30 24 4.69 2.58 0.55 855 4.52 2.48 0.55 902 4.41 2.43 0.55 931 4.27 2.35 0.55 978
30 26 4.83 2.08 0.43 902 4.69 2.02 0.43 949 4.62 1.99 0.43 978 4.48 1.93 0.43 1006
31 18 4.11 3.91 0.95 752 3.94 3.74 0.95 790 3.78 3.59 0.95 827 3.64 3.46 0.95 865
31 20 4.29 3.56 0.83 790 4.11 3.41 0.83 837 3.99 3.31 0.83 855 3.85 3.20 0.83 893
31 22 4.46 3.17 0.71 818 4.31 3.06 0.71 870 4.20 2.98 0.71 893 4.03 2.86 0.71 931
31 24 4.69 2.77 0.59 855 4.52 2.66 0.59 902 4.41 2.60 0.59 931 4.27 2.52 0.59 978
31 26 4.83 2.27 0.47 902 4.69 2.20 0.47 949 4.62 2.17 0.47 978 4.48 2.11 0.47 1006
32 18 4.11 4.07 0.99 752 3.94 3.90 0.99 790 3.78 3.74 0.99 827 3.64 3.60 0.99 865
32 20 4.29 3.73 0.87 790 4.11 3.58 0.87 837 3.99 3.47 0.87 855 3.85 3.35 0.87 893
32 22 4.46 3.35 0.75 818 4.31 3.23 0.75 870 4.20 3.15 0.75 893 4.03 3.02 0.75 931
32 24 4.69 2.95 0.63 855 4.52 2.84 0.63 902 4.41 2.78 0.63 931 4.27 2.69 0.63 978
32 26 4.83 2.46 0.51 902 4.69 2.39 0.51 949 4.62 2.36 0.51 978 4.48 2.28 0.51 1006
NOTE Q : Total capacity (kW) SHF : Sensible heat factor DB : Dry-bulb temperature
SHC : Sensible heat capacity (kW) INPUT : Total power input (W) WB : Wet-bulb temperature
OBH668

17
PERFORMANCE DATA COOL operation at Rated frequency
MUFZ-KJ35VEHZ
CAPACITY: 3.5 kW SHF: 0.73 INPUT: 940 W
INDOOR
DB (°C)
INDOOR
WB (°C)
OUTDOOR DB (°C)
35 40 46
Q SHC SHF INPUT Q SHC SHF INPUT Q SHC SHF INPUT
21 18 3.43 1.89 0.55 921 3.15 1.73 0.55 978 2.91 1.60 0.55 1015
21 20 3.61 1.55 0.43 959 3.36 1.44 0.43 1006 3.12 1.34 0.43 1062
22 18 3.43 2.02 0.59 921 3.15 1.86 0.59 978 2.91 1.71 0.59 1015
22 20 3.61 1.69 0.47 959 3.36 1.58 0.47 1006 3.12 1.46 0.47 1062
22 22 3.82 1.34 0.35 996 3.57 1.25 0.35 1053 3.33 1.16 0.35 1090
23 18 3.43 2.16 0.63 921 3.15 1.98 0.63 978 2.91 1.83 0.63 1015
23 20 3.61 1.84 0.51 959 3.36 1.71 0.51 1006 3.12 1.59 0.51 1062
23 22 3.82 1.49 0.39 996 3.57 1.39 0.39 1053 3.33 1.30 0.39 1090
24 18 3.43 2.30 0.67 921 3.15 2.11 0.67 978 2.91 1.95 0.67 1015
24 20 3.61 1.98 0.55 959 3.36 1.85 0.55 1006 3.12 1.71 0.55 1062
24 22 3.82 1.64 0.43 996 3.57 1.54 0.43 1053 3.33 1.43 0.43 1090
24 24 4.03 1.25 0.31 1034 3.78 1.17 0.31 1081 3.57 1.11 0.31 1128
25 18 3.43 2.44 0.71 921 3.15 2.24 0.71 978 2.91 2.06 0.71 1015
25 20 3.61 2.13 0.59 959 3.36 1.98 0.59 1006 3.12 1.84 0.59 1062
25 22 3.82 1.79 0.47 996 3.57 1.68 0.47 1053 3.33 1.56 0.47 1090
25 24 4.03 1.41 0.35 1034 3.78 1.32 0.35 1081 3.57 1.25 0.35 1128
26 18 3.43 2.57 0.75 921 3.15 2.36 0.75 978 2.91 2.18 0.75 1015
26 20 3.61 2.27 0.63 959 3.36 2.12 0.63 1006 3.12 1.96 0.63 1062
26 22 3.82 1.95 0.51 996 3.57 1.82 0.51 1053 3.33 1.70 0.51 1090
26 24 4.03 1.57 0.39 1034 3.78 1.47 0.39 1081 3.57 1.39 0.39 1128
26 26 4.24 1.14 0.27 1072 3.99 1.08 0.27 1119 3.75 1.01 0.27 1166
27 18 3.43 2.71 0.79 921 3.15 2.49 0.79 978 2.91 2.29 0.79 1015
27 20 3.61 2.42 0.67 959 3.36 2.25 0.67 1006 3.12 2.09 0.67 1062
27 22 3.82 2.10 0.55 996 3.57 1.96 0.55 1053 3.33 1.83 0.55 1090
27 24 4.03 1.73 0.43 1034 3.78 1.63 0.43 1081 3.57 1.54 0.43 1128
27 26 4.24 1.31 0.31 1072 3.99 1.24 0.31 1119 3.75 1.16 0.31 1166
28 18 3.43 2.85 0.83 921 3.15 2.61 0.83 978 2.91 2.41 0.83 1015
28 20 3.61 2.56 0.71 959 3.36 2.39 0.71 1006 3.12 2.21 0.71 1062
28 22 3.82 2.25 0.59 996 3.57 2.11 0.59 1053 3.33 1.96 0.59 1090
28 24 4.03 1.89 0.47 1034 3.78 1.78 0.47 1081 3.57 1.68 0.47 1128
28 26 4.24 1.48 0.35 1072 3.99 1.40 0.35 1119 3.75 1.31 0.35 1166
29 18 3.43 2.98 0.87 921 3.15 2.74 0.87 978 2.91 2.53 0.87 1015
29 20 3.61 2.70 0.75 959 3.36 2.52 0.75 1006 3.12 2.34 0.75 1062
29 22 3.82 2.40 0.63 996 3.57 2.25 0.63 1053 3.33 2.09 0.63 1090
29 24 4.03 2.05 0.51 1034 3.78 1.93 0.51 1081 3.57 1.82 0.51 1128
29 26 4.24 1.65 0.39 1072 3.99 1.56 0.39 1119 3.75 1.46 0.39 1166
30 18 3.43 3.12 0.91 921 3.15 2.87 0.91 978 2.91 2.64 0.91 1015
30 20 3.61 2.85 0.79 959 3.36 2.65 0.79 1006 3.12 2.46 0.79 1062
30 22 3.82 2.56 0.67 996 3.57 2.39 0.67 1053 3.33 2.23 0.67 1090
30 24 4.03 2.21 0.55 1034 3.78 2.08 0.55 1081 3.57 1.96 0.55 1128
30 26 4.24 1.82 0.43 1072 3.99 1.72 0.43 1119 3.75 1.61 0.43 1166
31 18 3.43 3.26 0.95 921 3.15 2.99 0.95 978 2.91 2.76 0.95 1015
31 20 3.61 2.99 0.83 959 3.36 2.79 0.83 1006 3.12 2.59 0.83 1062
31 22 3.82 2.71 0.71 996 3.57 2.53 0.71 1053 3.33 2.36 0.71 1090
31 24 4.03 2.37 0.59 1034 3.78 2.23 0.59 1081 3.57 2.11 0.59 1128
31 26 4.24 1.99 0.47 1072 3.99 1.88 0.47 1119 3.75 1.76 0.47 1166
32 18 3.43 3.40 0.99 921 3.15 3.12 0.99 978 2.91 2.88 0.99 1015
32 20 3.61 3.14 0.87 959 3.36 2.92 0.87 1006 3.12 2.71 0.87 1062
32 22 3.82 2.86 0.75 996 3.57 2.68 0.75 1053 3.33 2.49 0.75 1090
32 24 4.03 2.54 0.63 1034 3.78 2.38 0.63 1081 3.57 2.25 0.63 1128
32 26 4.24 2.16 0.51 1072 3.99 2.03 0.51 1119 3.75 1.91 0.51 1166
NOTE Q : Total capacity (kW) SHF : Sensible heat factor DB : Dry-bulb temperature
SHC : Sensible heat capacity (kW) INPUT : Total power input (W) WB : Wet-bulb temperature
OBH668

18
PERFORMANCE DATA HEAT operation at Rated frequency
MUFZ-KJ25VEHZ
CAPACITY: 3.4 kW INPUT: 770 W
INDOOR
DB (°C)
OUTDOOR WB (°C)
-10 -5 0 5 10 15 20
Q INPUT Q INPUT Q INPUT Q INPUT Q INPUT Q INPUT Q INPUT
15 2.14 501 2.58 601 3.03 678 3.47 732 3.91 778 4.32 801 4.76 816
21 2.04 539 2.45 639 2.89 708 3.30 762 3.74 801 4.15 824 4.57 855
26 1.84 578 2.28 678 2.69 747 3.13 801 3.57 839 3.98 862 4.42 886
MUFZ-KJ35VEHZ
CAPACITY: 4.3 kW INPUT: 1100 W
INDOOR
DB (°C)
OUTDOOR WB (°C)
-10 -5 0 5 10 15 20
Q INPUT Q INPUT Q INPUT Q INPUT Q INPUT Q INPUT Q INPUT
15 2.71 715 3.27 858 3.83 968 4.39 1045 4.95 1111 5.46 1144 6.02 1166
21 2.58 770 3.10 913 3.66 1012 4.17 1089 4.73 1144 5.25 1177 5.78 1221
26 2.32 825 2.88 968 3.40 1067 3.96 1144 4.52 1199 5.03 1232 5.59 1265
NOTE: Q: Total capacity (kW) INPUT : Total power input (W) DB: Dry-bulb temperature WB: Wet-bulb temperature
OBH668

19
MUFZ-KJ25VEHZ
MUFZ-KJ35VEHZ
9-2. R.V. COIL CONTROL
Heating . . . . . . . . . . . . . . . . . ON
Cooling . . . . . . . . . . . . . . . . . OFF
Dry . . . . . . . . . . . . . . . . . . . . OFF
NOTE: The 4-way valve reverses for 5 seconds right before start-up of the compressor.
ON
OFF
ON
OFF
Outdoor fan
motor
Compressor
5 seconds 15 seconds
ON
OFF
Compressor
Outdoor fan
motor
R.V.coil ON
OFF
ON
OFF
<COOL>
5 seconds
<HEAT>
5 seconds
9-1. 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.
9-3. RELATION BETWEEN MAIN SENSOR AND ACTUATOR
Sensor Purpose
Actuator
Compressor LEV Outdoor fan
motor R.V.coil Indoor fan motor
Defrost
heater
Discharge temperature
thermistor Protection ○○
Indoor coil temperature
thermistor
Cooling: Coil frost prevention ○
Heating: High pressure protec-
tion ○○
Defrost thermistor Heating: Defrosting ○○○○○
Fin temperature thermistor Protection ○○
Ambient temperature
thermistor
Cooling: Low ambient tempera-
ture operation ○○○
Heating: Defrosting (Heater) ○
Outdoor heat exchanger tem-
perature thermistor
Cooling: Low ambient tempera-
ture operation ○○○
Cooling: High pressure protec-
tion ○○○
ACTUATOR CONTROL
9
OBH668

20
10-1. 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 11-6-1.)
Jumper wire Defrost finish temperature (°C)
JS Soldered (Initial setting) 8
None (Cut) 15
10-2. PRE-HEAT CONTROL SETTING
PRE-HEAT CONTROL
When moisture gets into the refrigerant cycle, it may interfere the start-up of the compressor at low discharge tempera-
ture. The pre-heat control prevents this interference. The pre-heat control turns ON when the discharge temperature is
20°C or below. When the pre-heat control turns ON, the compressor is energized. (About 50 W)
Pre-heat control setting
<JK>
ON: To activate the pre-heat control, cut JK wire of the inverter P.C. board.
OFF: To deactivate the pre-heat control, solder JK wire of the inverter P.C. board.
(Refer to 11-6.1)
NOTE: When the inverter P.C. board is replaced, check JK wire, and cut/solder it if necessary.
MUFZ-KJ25VEHZ
MUFZ-KJ35VEHZ
SERVICE FUNCTIONS
10
OBH668