Mitsubishi Mr.Slim MFZ-KA09NA User manual

TM
INDOOR UNIT
SERVICE MANUAL
INDOOR UNIT
Models
MFZ-KA09NA
MFZ-KA12NA
MFZ-KA18NA
No. OBH568
REVISED EDITION-A
Please void OBH568.
Revision A:
• OUTLINES AND DIMENSIONS has
been corrected.
• Some descriptions have been modified.
MFZ-KA09NA
MFZ-KA12NA
MFZ-KA18NA
Outdoor unit service manual
MXZ-B NA Series (OBH560)
CONTENTS
1. TECHNICAL CHANGES······································· 2
2. PART NAMES AND FUNCTIONS·····················2
3. SPECIFICATION················································4
4. OUTLINES AND DIMENSIONS ························ 5
5. WIRING DIAGRAM············································ 6
6. REFRIGERANT SYSTEM DIAGRAM···············7
7. SERVICE FUNCTIONS ·····································8
8. MICROPROCESSOR CONTROL ··················· 10
9. TROUBLESHOOTING·····································16
10. DISASSEMBLY INSTRUCTIONS····················30
PARTS CATALOG (OBB568)
NOTE:
RoHS compliant products have <G> mark on
the spec name plate.

2
MFZ-KA09NA MFZ-KA12NA MFZ-KA18NA
1. New model
1TECHNICAL CHANGES
MFZ-KA09NA MFZ-KA12NA MFZ-KA18NA
2PART NAMES AND FUNCTIONS
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
Revision A:
• OUTLINES AND DIMENSIONS has been corrected.
• Some descriptions have been modified.
OBH568A

3
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-KA09NA
MFZ-KA12NA
1
1
2
1
2
2
1
5
4
4
1
1
1
MFZ-KA18NA
ON-TIMER button
CLOCK SET button
TIME SET buttons
FORWARD button
BACKWARD button
OFF-TIMER button
SMART SET 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
MFZ-KA09NA MFZ-KA12NA MFZ-KA18NA
OBH568A

4
Indoor model MFZ-KA09NA MFZ-KA12NA MFZ-KA18NA
Power supply V, phase, Hz 208/230, 1, 60
Max. fuse size (time delay)/ Disconnect switch A15
Airflow
Super High - High - Med. -
Low - Quiet
COOL Dry
(Wet)
CFM 314-251-205-169
(303-241-197-163)
321-261-215-177
(309-252-207-170)
394-325-279-251
(379-313-269-241)
HEAT Dry CFM 332-219-198-177 335-219-201-184 434-297-275-261
Sound level
Super High - High - Med. -
Low - Quiet
Cooling dB(A) 40-35-30-25 41-36-31-26 46-42-38-35
Heating dB(A) 41-36-31-28 47-42-38-35
Cond. drain connection O.D. in. 5/8
Dimensions
W
in.
27-9/16
D 7-7/8
H 23-5/8
Weight Ib. 32
External finish White
Control voltage (by built-in transformer) 12 - 24 VDC
NOTE: Test conditions are based on ARI 210/240.
3SPECIFICATION
3-2. OUTLET AIR SPEED AND COVERAGE
●The air coverage is the figure up to the
position where the air speed is 1 ft./s.,
when air is blown out horizontally from
the unit properly at the High speed posi-
tion.
The coverage should be used only as a
general guideline since it varies accord-
ing to the size of the room and furniture
arranged inside the room.
(2) OPERATION
Mode Condition
Intake air temperature (°F)
Indoor Outdoor
DB WB DB WB
Cooling
Standard temperature 80 67 95 —
Maximum temperature 90 73 115 —
Minimum temperature 67 57 14 —
Maximum humidity 78% —
Heating
Standard temperature 70 60 47 43
Maximum temperature 80 67 75 65
Minimum temperature 70 60 6 5
3-1. OPERATING RANGE
(1) POWER SUPPLY
Rated voltage Guaranteed voltage (V)
Indoor unit
208/230 V
1 phase
60 Hz
Min. 198 208 230 Max. 253
Model Mode Function Airflow
(CFM)
Air speed
(ft./s.)
Coverage (ft.)
MFZ-KA09NA
HEAT Dry 332 6.6 15.4
COOL Dry 314 6.3 14.6
Wet 303 6.1 14.2
MFZ-KA12NA
HEAT Dry 335 6.7 15.6
COOL Dry 321 6.4 15.0
Wet 309 6.2 14.5
MFZ-KA18NA
HEAT Dry 434 8.7 20.0
COOL Dry 395 7.9 18.3
Wet 379 7.5 17.5
OBH568A

5
4OUTLINES AND DIMENSIONS
2-3/8
15/32
3/4 2-3/8
4-15/16
5-25/32
17-7/86-1/8
2-3/8
1-6/16
1-25/32
4-5/16
3-5/32
2-3/8
2-27/32
13-9/32 13-9/32
14-5/16
13-1/88-9/32 23-11/32 9/32
5-5/32 5-5/32
4- 1/4 Hole
Indoor unit
Installation plate
3-3/4
4-27/32
4-15/16
2-3/8
3/4
15/32
2-3/8
5-1/16
4-5/8
6-1/2
8-1/16
7-7/815/32
15/32
7/16
Gas pipe
09, 12: 3/8(flared)
18: 1/2(flared)
Liquid pipe
1/4(flared)
drain
Air in
Air out
Air out
1-27/32 1-27/32
23-5/8
27-9/16
2-1/8 20 5-13/32
23-29/32
More than 3-7/8
More than
3-7/8 More than
3-7/8
MFZ-KA09NA MFZ-KA12NA MFZ-KA18NA Unit: inch
OBH568A

6
MFZ-KA09NA MFZ-KA12NA MFZ-KA18NA
5WIRING DIAGRAM
OBH568A

7
MFZ-KA09NA MFZ-KA12NA MFZ-KA18NA
Unit: inch
6REFRIGERANT SYSTEM DIAGRAM
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 3/8 (MFZ-KA09/12NA)
Refrigerant pipe 1/2 (MFZ-KA18NA)
(with heat insulator)
Refrigerant pipe 1/4
(with heat insulator)
Indoor coil
thermistor
RT12 (main)
Distributor
OBH568A

8
MFZ-KA09NA MFZ-KA12NA MFZ-KA18NA
7SERVICE FUNCTIONS
7-1. TIMER SHORT MODE
For service, the following set time can be shortened by bridging of JPG and JPS on the electronic control P.C. board.
(Refer to 9-7.)
Set time: 3-minutes 3-seconds (It takes 3 minutes for the compressor to start operation. However, the starting time is
shortened by bridging of JPG and JPS.)
7-2. P.C. BOARD MODIFICATION FOR INDIVIDUAL OPERATION
A maximum of 4 indoor units with wireless remote controllers can be used in a room.
In this case, to operate each indoor unit individually by each remote controller, both the P.C. boards of remote controller
and the electronic control P.C. boards must be modified according to the number of the indoor unit.
How to modify the remote controller P.C. board
Remove batteries before modification.
The board has a print as shown below :
NOTE: For modification, take out the batter-
ies and push the OPERATE/STOP
(ON/OFF) button 2 or 3 times at
first.
After finish modification, put back
the batteries then press the RESET
button.
The P.C. board has the print “J1” and “J2”. Solder “J1” and “J2” according to the number of indoor unit as shown in Table 1.
After modification, press the RESET button.
How to modify the electronic control P.C. board
Turn OFF the power supply before modification. Cut off “JR05” and “JR06” on the electronic control P.C. board according
to the number of indoor unit as shown in Table 2. (Refer to 9-7.)
No. 1 unit
No. 2 unit
No. 3 unit
No. 4 unit
1 unit operation
No modification
–
–
–
2 units operation
Same as at left
Solder J1
–
–
3 units operation
Same as at left
Same as at left
Solder J2
–
4 units operation
Same as at left
Same as at left
Same as at left
Solder both J1 and J2
No. 1 unit
No. 2 unit
No. 3 unit
No. 4 unit
JR05
No modification
Cut off JR05
No modification
Cut off JR05
JR06
No modification
No modification
Cut off JR06
Cut off JR06
JR06
JR05
CN211
Fuse (F11)
IC101
T11
VARISTOR (NR11)
Indoor electronic
control P.C. Board
CN212
CN151
CN152
CN1X1 CN1Y1
C111
R111
Table 1
Table 2
Remote controller model: KM05G
J2
J1
NOTE: After modification, turn ON the power supply and with the remote controller headed towards the indoor unit, press the
OPERATE/STOP (ON/OFF) button. If 1 or 2 beeps is heard from the indoor unit, modification is completed correctly.
OBH568A

9
NOTE:
• The operation settings are memorized when 10 seconds have passed after the indoor unit was operated with the remote
controller.
• If main power is turned OFF or a power failure occurs while AUTO START/STOP timer is active, the timer setting is
cancelled.
• If the unit has been turned OFF with the remote controller before power failure, the auto restart function does not work
as the power button of the remote controller is OFF.
• To prevent breaker tripping due to the rush of starting current, systematize other home appliance not to turn ON at the
same time.
• When some air conditioners are connected to the same supply system, if they are operated before power failure, the
starting current of all the compressors may flow simultaneously at restart.
Therefore, the special counter-measures are required to prevent the main voltage-drop or the rush of the starting current
by adding to the system that allows the units to start one by one.
How to release “AUTO RESTART FUNCTION”
Turn off the main power for the unit.
Solder the Jumper wire to JR07 on the indoor electronic control P.C. board. (Refer to 9-7.)
JR07
CN106
CN111 CN112 CN113
CN125
C111 T11
CN212
CN211
CN152
CN151
IC101
F11
Operation
If the main power has been cut, the operation settings remain.
After the power is restored, the unit restarts automatically according to the memory.
(However, it takes at least 3 minutes for the compressor to start running.)
7-3. AUTO RESTART FUNCTION
When the indoor unit is controlled with the remote controller, the operation mode, the set temperature, and the fan speed
are memorized by the indoor electronic control P.C. board. The “AUTO RESTART FUNCTION” sets to work the moment
power is restored after power failure. Then, the unit will restart automatically.
OBH568A

10
MFZ-KA09NA MFZ-KA12NA MFZ-KA18NA
8MICROPROCESSOR CONTROL
8-1. COOL ( ) OPERATION
(1) Press OPERATE/STOP (ON/OFF) button.
OPERATION INDICATOR lamp of the indoor unit turns ON with a beep tone.
(2) Select COOL mode with OPERATION SELECT button.
(3) Press TEMPERATURE buttons (TOO WARM or TOO COOL button) to select the desired temperature.
The setting range is 61 ~ 88°F (16 ~ 31°C).
Once the operation mode is set, the same operation mode can be repeated by simply turning OPERATE/STOP (ON/OFF) but-
ton ON.
Indoor unit receives the signal with a beep tone.
When the system turns OFF, 3-minute time delay will operate to protect system from overload and compressor will not restart
for 3 minutes.
WIRELESS REMOTE CONTROLLER
.)
.)
ra w.)
ON-TIMER button
CLOCK SET button
TIME SET buttons
FORWARD button
BACKWARD button
OFF-TIMER button
SMART SET button
RESET button
VANE CONTROL button
Signal transmitting section
Operation display section
Temperature buttons
OPERATE/STOP
(ON/OFF) button
FAN SPEED CONTROL button
OPERATION SELECT button
ECONO COOL button
Indication of
remote controller
model is on back
OBH568A