Mitsubishi Electric PKFY-20VAM Operating manual

TECHNICAL & SERVICE MANUAL
SPLIT-TYPE,HEAT PUMP AIR CONDITIONERS
CONTENTS
1. PART NAMES AND FUNCTIONS········2
2. SPECIFICATION···································4
3. OUTLINES AND DIMENSIONS············6
4. WIRING DIAGRAM·······························7
5. REFRIGERANT SYSTEM DIAGRAM ··8
6. TROUBLESHOOTING··························9
7. DISASSEMBLY PROCEDURE···········14
8. PARTS LIST········································17
<Indoor unit>
PKFY-20VAM
PKFY-25VAM
No. OC112
1997
Models
Wall Mounted
Series PKFY
INDOOR UNIT
MODEL NAME
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2
PART NAMES AND FUNCTIONS
1
● Indoor Unit
● Remote controller [PAR-F25MA]
● Once the operation of the unit is set, subsequent operations can only be performed by pressing the ON/OFF button
repeatedly.
TIMER button
This switches between continuous
operation and the timer operation
AIR SPEED button
The sets the ventilation fan speed.
● Operation buttons
TIMER SETTING button
This sets or switches the current
time, start time and stop time.
OPERATION SWITCH button
Press this button to switch the cooler
electronic dry (denumidity), automat-
ic and heater modes.
TEMP ADJUSTMENT button
This sets the room temperature. The
temperature setting can be per-
formed in 1°C units.
Setting range :
Cooler 19°C to 30°C
Heater 17°C to 28°C
CHECK-TEST RUN button
Only press this button to perform an
inspection check or test operation.
Do not use it for nomal operation
FILTER button
This resets the filter service indica-
tion display
AIR DIRECTION button
This adjusts the vertical angle of the
ventilation.
ON/OFF button
This switches between the operation
and stop modes each time it is
pressed. The lamp on this button
lights during operation.
The model name of the remote con-
troller is indicated.
LOUVER button
This switches the horizontal fan
motion ON and OFF.
(This button does not operate in this
model.)
Air intake grille Air intake
Guide vane Air Outlet
Aute Vane
Filter
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3
Caution
●Only the / display lights when the unit is stopped and power supplied to the unit.
●“NOT AVAILABLE” is displayed when the AIR DIRECTION button are pressed.This indicates that this room unit is not
equipped with the fan dieection adjustment function and the louver function.
● When the power is turned on, “‘HO” is indicated on the room temperature indication area for a while (maximum for 2
minute). It does not indicate a malfunction. Operation the unit after “‘HO” indication disappear.
● When power is turned ON for the first time, it is normal that “HO” is displayed on the room temperature indication(For max.
2minutes.) Please wait until this “HO” indication disappear then start the operation.
CENTRALLY
CONTROLLED display
This indicates when the unit is con-
trolled by optional features such as
central control type remote controller.
TIMER display
This indicates when the continous
operation and time operation modes
are set.
It also display the time for the timer
operation at the same time as when
it is set.
OPERATION MODE display
This indicates the operation mode.
STANDBY display
This indicates when the standby
mode is set from the time the sleep
operation starts until the heating air
is discharged.
DEFROST display
This indicates when the defrost oper-
ation is performed.
CHECK display
This indicates when a malfunction
has occurred in the unit which should
be checked.
CLOCK display
The current time , start time and stop
time can be displayed in tensecond
intervals by pressing the time switch
button. The start time or stop time is
always displayed during the timer
operation.
●Display
In this display example on the bot-
tom left, a condition where all dis-
play lamps light is shown for expla-
nation purposes although this differs
from actual operation.
Operation lamp
This lamp lights during operation,
goes off when the unit stops and
flashes when amalfunction occurs.
POWER display
This lamp lights when electricity is
supplied to the unit.
SET TEMPERATURE display
This displays the selected setting
temperature.
AIR DIRECTION display
This displays the air direction.
ROOM TEMPERATURE display
The temperature of the suction air is
displayed during operation. The dis-
play range is 8° to 39°C. The display
flashes 8°C when the actual temper-
ature is less than 8° and flashes
39°C when the actual temperature is
greater than 39°C.
display
This display lights in the check mode
or when a test operation is per-
formed.
CHECK MODE
TEST RUN
This lamp lights when the filter need
to be cleaned.
AIR SPEED display
The selected fan speed is displayed.
FILTER display
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4
2SPECIFICATION
2-1 Specification
Power Supply
Starting Current
Fanx No.
Air flow Note2
External stafic pressure
Fan motor output
Item
Power
Cooling capacity
Heating capacity
Exterior <munsell symbol>
Out dimensions
Heat exchanger
Fan
Insulator
Air filter
Pipe dimensions
Drain pipe size
Noise level
Product weight
Unit
V · Hz
Z/h
Z/h
kW
kW
A
A
—
mm
mm
mm
—
—
k/min
Pa
kW
—
—
[mm
[mm
[mm
dB (A)
kg
Cooling
Heating
Cooling
Heating
Height
Width
Depth
Gas side
Liquid side
PKFY-20VAM
2000
2250
PKFY-25VAM
2500
2800
Single phase 220V-240V 50Hz
0.04
0.04
0.20
0.20
Plastic munsell : <2.60Y 8.66/0.69>
295
815
158
Cross fin
Lineflow fan ✕1
5.9-5.6-5.2-4.9
0
0.017
Polyethylene sheet
PP honey comb
12.7 <1 / 2F>
6.35 <1 / 4F>
Outer dimeter [28 Outer diameter of the connection
36-35-33-32
8.5
Electric
characteristic
Note 1. Rating conditions (JIS B8616)
Cooling :Indoor 27°C DB. 19.5°C WB
Outdoor 35°C DB. 24°C WB
Heating : Indoor 20°C DB.
Outdoor 7°C DB. 6°C WB
Note 2. Air flow and the noise level are indicated as High-Middium 1-Middium2-Low.
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5
2-2 Electrical parts specifications
Model
Transformer
Room temperature thermistor
Liquid pipe
thermistor
Gas pipe
thermistor
Fuse
(Indoor controller board)
Fan motor
(with thermal fuse)
Fan motor capacitor
Vane motor
(with limit switch)
Liner expansion valve
Power supply terminal block
Transmission terminal block
Symbol
T
TH21
TH22
TH23
FUSE
MF1,2
C1
MV
LEV
TB2
TB5
(Primary) 50/60Hz 220-240V (Secondry) (18.4V 1.2A)
Resistance:
0¡C / 15k½, 10¡C / 9.6k½, 20¡C / 6.3k½, 25¡C / 5.4k½, 30¡C / 4.3k½, 40¡C / 3.0k½
Resistance:
0¡C/15k½, 10¡C/9.6k½, 20¡C/6.3k½, 25¡C/5.4k½, 30¡C/4.3k½, 40¡C/3.0k½
250V 6.3A
4-Pole Output 17W / RC4V17
1.5µF ✕440V
MSFBC20A76 DC12V
DC12V Stepping motor drive
Port [3.2 (0~2000pulse) EDM-402ME
(L, N, ;) 264V 20A
(M1, M2,S ) 250V 10A
PKFY-20VAM/PKFY-25VAM
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6
3OUTLINES AND DIMENSIONS
Unit : mm
783
C
D
A
B
C B A D
25.5
159
407.5
328328
298
235
235
205
205
175
175
170
170
10
10
0
298
407.5
168 135 125 110 35 10 27.5 40 53 65 87 113 128 0
295
260
260
225
225
190
190
180
159
155
155
120
120
85
85
30
30
45
44 50
0
133
122.5
97.5
85 60
47.5 22.5
15 90
102.5
124
4-4.5✕35
4-4.5✕40 4-4.5✕37
4-11✕20
8- 4.3
0
72.5
13
Air intake dimension
Air intake Installation plate
Knock out hole
Installation space
100 or more
20 or more
20 or more
130 or more
Address board
Drain pipe
Liquid pipe Flare connection 1/4F
Flare connection 1/2F
Insulation out dimention 28
Insulation Out dimention 35 Gas pipe
Refrigrant pipe
Address board is protected by the plastic cover. For the setting, remark 1-screw using the screw driver.
Installation plate
Air intake dimension
Air intake dimension
Air outlet dimension
Drain pipe length
Gas pipe
Detail of Terminal block
Terminal block for remote controller
Terminal block for remote controller Terminal block for power supply address board
Air outlet angle
Air outlet dimention
Air outlet direction
Detail of address board
Dip swich
Terminal block
Terminal block for power supply
Knock out hole for right - hand side piping
Knock out hole for left - hand side piping
Knock out hole for under piping
Liquid pipe
815
630 695
660
450
520
54
50
16
45 91.5 10 34
2.5
2.5 16
4 50
10
45
5
45
3
R15
R15
R15
R12
R8
R8
R8
10
24.4
116
110
60
146
295
21.5
247.5
150 158
70.3
37.4
5
2.5 60
13
80
4- 9
12- 2.8 87- 5.1 65
17
3
1
1
Note1.For the instalation, be sure to leave some space in case there is finge at edge of the celing. Note2. Use the M10 or W3/8 bolt for the istallation plate. Note3. Refer for the specification table it below .
Detail of knock out hole (A B C)
Connection out dimention 28
Lotary switch(part No.)
Lotary switch(self address)
Secondry
Primary
Knock out hole for the remote controller wiring
Knock out hole for the remote controller wiring
Control wire (30v)
: Follow the instruction stated at Note3 for the connection with the control wire. : There is no terminal board for contlroller.
54 or more for left
or left back piping
Unit transplant parts
pipe hole
Position detail of the tapping screw and bats at pipe intake
Center of gravity hole for installation
Air intake dimention
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7
WIRING DIAGRAM4
MODELS : PKFY-20VAM, PKFY-25VAM
Legend
Symbol Name
TH23 Gas pipe thermistor
(0°C / 15kΩ, 25°C / 5.4kΩ)
P.B Indoor power board
ZNR Varistor
FUSE Fuse (6.3A)
F.C Fan phase control
T Transformer
MF Fan motor
C1 Fan motor capacitor
MV Vane motor
LEV Linear expansion valve
Symbol Name
M.B
CN32 Indoor controller board Remote switch connector
CN41 HA terminal — A connector
CN51 Centrally control connector
CN52 Remote indication connector
SW2 Capacity cord switch
SW3 Function selector
TH21 Room temperature thermistor
(0°C / 15kΩ, 25°C / 5.4kΩ)
TH22 Liquid pipe thermistor.
(0°C / 15kΩ, 25°C / 5.4kΩ)
Symbol Name
TB2
TB5 Power supply terminal block Transmission terminal block
A.B Address board
SW1 <A.B> Mode selector
SW5 <A.B> Voltage selector
SW11 <A.B> 1st digit address setting
SW12 <A.B> 2nd digit address setting
SW14 <A.B> Connection No. setting
T O NEXT
INDOOR UNIT
PULL
BOX
FUSE
(15A)
BREAKER
(15A)
AC220-240V
SW5
220V 240V
BLU
RED
BLU BLU
WHT
BLK RED BLU
00
M2
M1 REMOTE CONTROLLER
DC24-30V
{
BC CONTROLLER
T O OUTDOOR UNIT
S(SHIELD)
GRN/YEL
~/N 220-240VA@50Hz
POWER SUPPLY
N
TB2
L
MICON
BOARD
(WHT)
POWER BOARD
ADDRESS
(RED)
(WHT)
REMOTE
INDICATION
CONNECTION
NO.
1ST
DIGIT
2ND
DIGIT
3RD
DIGIT
ADDRESS
(RED)
F.C ZNR
3
1
P.B
See fig:❈1
BLU
YEL
ORN
PNK
WHT
YEL
MF
5
TH21TH23 TH22
LEV ORN
BLU
RED
RED
BRN
MV
LED5
0
A.B
SW14
SW11SW12
SW1
10987654321
OFF
ON 1
1
8
(RED)
ADDRESS
CN43
CN82
44
8
6.3A
250V
FUSE
AC18.4V
T
C1
CND
(RED)
(GRN)
FAN1 12
1 3 5
1 2
(BLU)
M-NET
CN2M
1 2
LIQUID
CN21
CN53-P
MICON
BOARD
CN35-P
1
5
M.B
POWER BOARD
CN53-M 1 5
3
CN35-M 1
LED4 LED3 LED2 LED1
SW2
4321
0N
0FF
SW3
10987654321
5
1
CENTRALLY
CONTROL
CN51
54
11
(WHT)
CN52 CN42
(RED)
ADDRESS
18
CN81
(RED)
INTAKE
CN20
21
(WHT)
CN60
LEV (BLK)
GAS
CN29
(GRN)
REVOLUTION
CN33
2
61 1
6
123
CN32
REMOTE
SWITCH
(WHT)
123
1 2 3 4
HA
CN41
(WHT)
(BLU)
CN5V
51
TB5
Note
1. At servicing for outdoor unit, always follow the wiring diagram of outdoor unit.
2. Symbol [S] of TB5 is the shield wire connection.
3. Symbols used in wiring diagram above are, /: terminal block, [: connector, ●: direct wire connection.
4. The setting of the SW2 dip switches differs in the capacity for the detail, see the table below.
5. Please set the switch SW5 accordng to the power supply voltage.
SW5 to 240V side when the power supply is 230 and 240 volts.
When the power supply is 220 volts, set SW5 to 220V side.
[
ON
OFF 1234
MODELS SW2
PKFY-20VAM ON
OFF 1234
MODELS SW2
PKFY-25VAM
<❈1>
BG79N652H01
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8
5REFRIGERANT SYSTEM DIAGRAM
Strainer
(#100mesh)
Strainer
(#50mesh)
Heat exchanger
Room temperature thermistor
TH21
Gas pipe thermistor
TH23
Liquid pipe thermistor
TH22
Gas pipe
Flare
Linear expansion
valve
Gas pipe
PKFY-20VAM, PKFY-25VAM
{12.7 <1/2F>
Liquid pipe {6.35 <1/4F>
Models
Item
Refrigeration pipe size (Flare connection size)
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9
6TROUBLESHOOTING
6-1. How to check
Room temperature
thermistor(TH21)
Liquid pipe
thermistor(TH22)
Gas pipe
thermistor(TH23)
Vane motor
Fan motor
Linear expansion
valve
Disconnect the connector, then measure the resistance using a tester.
(Sorrounding temperature 10°C~30°C)
Part Name Check points
1Measure the resistance between the terminals using a tester.(Surrounding tempreture 20:.)
Disconnect the connector then measure the resistance valve using a tester.
(Coil temperature 20°C)
(Refer to the thermistor)
Normal Abnormal
White-Black 195'Open or short
Red-Black
Normal
Abnormal
!At first, check if the electrical pressure is 12V between the
brown wire(GND) and yellow wire(VCC).
@Slowly start running the fan. It is normal if while the fan rotate once,
the electrical pressure change from 0V to12V then go back to 0V.
If the electrical pressure stay at around 0V or 10V, it means the fan
motor has the defects.
200'
Normal
(1)-(5)
White-Red 150'±10%
Abnormal
Open or short
(2)-(6)
Yellow- Blown (3)-(5) Orange-Red (4)-(6) Blue-Brown
Normal
(1)-(2)
Red-Pink 400'±7%
Abnormal
Open or short
(1)-(3)
Red-Blue
(1)-(4)
red-Orange (1)-(5) Red-Yellow
White
Red
Black
Brown Blown Yellow
CN33
1
4
6
3 2 1
FAN1
1
2
3
4
5
6
LEV
White
Yellow
Orange
Blue
Red
Brown
CN60
2Without disassembling the parts, measure the electrical pressure of the gray wire(Signel line) and
brown wire (GND) While the power is on.
1Measure the resistance between the terminals using a tester.(Surrounding tempreture 25:.)
Normal
4.3k'~9.6k'
Abnormal
Open or short
OC112--1.qxp 11/16/98 4:46 PM Page 9

10
0
10
20
30
40
50
-20 -10 0 10 20 30 40 50
< Thermistor for lower temperature >
Temperature (:)
Resistance (K")
4[4
3
62
5
[3
2[2
1[1
[4
[3
[2
[1
Controller board
Drive circuit
Relay connector
Connector(CN60)
DC12V
Brown
Red
Blue
Orange
Yellow
White
5
1
3
4
6
M
4
6
2
3
5
1
Blue
Brown
Yellow
Orange
Red
White
Linear expansion valve
<Thermistor Characteristic graph>
Room temperature thermistor(TH21)
Liquid pipe thermistor(TH22)
Gas pipe thermistor(TH23)
Drain sensor(THD)
Thermistor R0=15k' ± 3%
Fixed number of B=3480k' ± 2%
Rt=15exp { 3480( ) }
0:15k'
10:9.6k'
20:6.3k'
25:5.2k'
30:4.3k'
40:3.0k'
Thermistor for
lower temperature
Linear expansion valve
①Operation summary of the linear expansion valve.
• Linear expansion valve open/close through stepping motor after receiving the pulse signal from the indoor controller board.
• Valve position can be changed in proportion to the number of pulse signal.
<Connection between the indoor controller board and the linear expasion valve>
1
273+t 1
273
Note : Since the number of the connector at the controller board side and the relay connector are different, follow the color of
the lead wire.
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11
Output
(Phase)
Output
{11
ON
{2ON
{3OFF
{4OFF
2
OFF
ON
ON
OFF
3
OFF
OFF
ON
ON
4
ON
OFF
OFF
ON
<Output pulse signal and the valve operation>
➁Linear expansion valve operation
➂Trouble shooting
D
A
E
B
C
Open
Extra tightning (80~100pulse)
Pulse number
2000 pulse
Opening a valve
all the way
Close
Valve position (capacity)
6
5
4
3
2
1
LED1k'
Symptom Check points
Operation circuit fail-
ure of the micro
processor.
Disconnect the connector on the controller board, then con-
nect LED for checking.
Pulse signal will be sent out for 10 seconds as soon as the
main switch is turn on. If there is LED with lights on or lights
off, it means the operation circuit is abnormal.
Countermeasures
Exchange the indoor con-
troller board at drive circuit
failure.
Linear expansion
valve mechanism is
locked.
Valve doesn't close
completely (thermis-
tor leaking).
Wrong connection of
the connector or
contact failure.
To check the linear expansion valve, operate the indoor unit
in fan mode and at the same time operate other indoor units
in cooling mode, then check the pipe temperature <liquid
pipe temperature> of the indoor unit by the
outdoor multi controller board operation
monitor. During fan operation, linear
expansion valve is closed completely and if
there are some leaking, detecting tempera-
ture of the thermistor will go lower. If the
detected temperature is much lower than
the temperature indicated in the remote
controller, it means the valve is not closed all the way. It is
not necessary to exchange the linear expansion valve, if the
leakage is small and not making any trouble.
Thermistor
Linear
expansion
valve
Motor will idle and make ticking noise when motor is operated
while the linear expansion valve is locked. This ticking sound
is the sign of the abnormality.
Check the color of lead wire and missing terminal of the con-
nector.
Exchange the linear
expansion vale.
Exchange the linear
expansion valve.
If large amount of thermis-
tor is leaked, exchange the
linear expansion valve.
Disconnect the connector
at the controller board,
then check the continuity.
Measure the resistance between the each coil (red-white,
red-orange, brown-yellow, brown-blue) using a tester. It is
normal if the resistance is in the range of 150'+10%.
Short or breakage of
the motor coil of the
linear expansion
valve.
Closing a valve : 1 → 2 → 3 → 4 → 1
Opening a valve : 4 → 3 → 2 → 1 → 4
The output pulse shift in above order.
❈ 1. When linear expasion valve operation stops, all output phase
become OFF.
2. At phase interruption or when phase does not shift in order,
motor does not rotate smoothly and motor lock, and vibrates.
❈ When the switch is turned on, 2200 pulse opening valve signal
will be send till it goes to Apoint in order to define the valve
position.
When the valve move smoothly, there is no noise or vibration
occurring from the linear expansion valve ; however, when the
pulse number moves from Eto Aor when the valve is locked,
more noise can be heard than normal situation.
❈ Noise can be detected by placing the ear against the screw dri-
ver handle while putting the screw driver to the linear expansion
valve.
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12
6-2. FUNCTION OF DIPSWITCH
PKFY-20VAM, PKFY-25VAM
1
2
3
4
5
6
7
8
9
10
1~4
1
2
3
4
5
6
7
8
9
10
Thermistor<Intake temperature>
position
ON OFF
Filter crogging ProvidedNot provided
Filter life 2,500hr 100hr
Air intake Effective Not effective
Remote indication switching Thermostat ON signal indication Fan output indication
Humidifier control Always operated while the heate is ON Operated depends on the condition
Air flow Low Extra low
Heat thermostat OFF Setting air flow Reset to SW1-7
Auto reset function Effective Not effective
Power ON/OFF Effective Not effective
Heat pump/Cool only Cooling only Heat pump
Louver Available Not available
Vane Available Not available
Vane swing function Available Not available
Vane holizontal angle Second setting First setting
Vane cooling limit angle setting Horizontal angle Down B,C
Effective Not effective
Heater 4deg up Not effective Effective
Target Superheat setting temperature 5deg 2deg
Target Sybcool setting temperature 15deg 10deg
ON
OFF 12345678910
ON
OFF 12345678910
ON
OFF 1234
ON
OFF 1234
PKFY-20VAM
MODEL SW2
PKFY-25VAM
Address board
<At delivery>
Indoor controller board
Indoor controller board
<At delivery>
SW3
Function
selection
SW2
Capacity
code
switch
SW1
Mode
selection
Switch Pole Function Operation by switch Remarks
Bult-in remote controller Indoor unit
Indoor linear expansion
valve opening
(Note1) Fan operation at Heating
mode
(Note2) Heater thermo ON is oper-
ating.
(Note3) SW1-7=OFF, SW1-8=ON
→Setting air flow.
SW1-7=OFF, SW1-8=ON
→Indoor fan stop.
Set while the unit is off.
<At delivery>
Set for each capacity.
Set while the unit is off.
(Note1) At cooling mode, each
angle can be used only 1
hour.
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13
0
5
9
4
8
3
7
2
6
1
SW12
10
0
5
9
4
8
3
7
2
6
1
SW11
1
0
8
F
7
E
6
D
5
C
4
B
3
A
2
9
1
SW14
0
5
9
4
8
3
7
2
6
1
SW12 0
5
9
4
8
3
7
2
6
1
SW11
0
8
F
7
E
6
D
5
C
4
B
3
A
2
9
1
SW14
Address board
Address board
Operation by switchSwitch Remarks
<At delivery>
<At delivery>
SW11
1st digit
address
setting
SW12
2st digit
address
setting
Rotary switch
SW14
Connector
No.
Setting
SW5
Voltage
selection
Rotary switch
Address setting should be done when network
remote controller (PAR-F25M) is being used.
This is the switch to be used when the indoor
unit is operated with R2, R3 series outdoor
unit as a set.
If the unit is used at the 230V or 240V area,
set the voltage to 240V.
If the unit is used at the 220V, set the voltage
to 220V.
Address can be set while the
unit is stopped.
Address board
2
220V 240V
<At delivery>
220V 240V
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14
7DISASSEMBLY PROCEDURE
OPERATION PROCEDURE PHOTOS & ILLUSTRATIONS
1. REMOVING THE LOWER SIDE OF THE INDOOR UNIT FROM
THE INSTALLATION PLATE
When there is removing plate
(1) Remove the corner box at right lower side of the indoor
unit.
(2) Remove the "Indoor unit removing plate" at the back side of
the corner box.
(3) Remove the hook by pulling the lower side of the indoor unit
down as shown in the figure 1.
When there is no removing plate or it can not be used for some
reason.
(1) Remove the front panel.
(2) Insert the screw driver to the corner hole at both left and
right side as shown in the figure 2.
(3) Push it up then, pull down the lower side of indoor unit and
remove the hook.
Indoor unit
removing plate
Insert
the edge Pull
Push Corner hole
1 2
Push Down
Be careful
not to damage
the airflow
adjustment
plate with the
screw driver.
PKFY-25VAM Be careful on removing heavy parts.
Figure 1 Figure 2
2. REMOVING THE FRONT PANEL
❈Before removing the front panel, leave the open space at
upper side of air flow adjustment plate approximately 2 to 3
cm.
(1) Remove the screw caps then remove the set screws.
(Refer to the photo 1)
(2) Remove the left side of the front panel, then right side.
(3) After removing the lower side of the front panel a little,
remove it as pulling the upper side toward you.
❈Please pay attention to the nozzle assemble.
INSTALLING THE FRONT PANEL
(1) Insert the lower side of the front panel under the air adjus-
ment plate.
(2) Set the upper side of the front panel.
(3) Set the lower side of the front panel then fix it with the
screws.
(4) Press the area indicated as arrow sign and set it to the air
conditioner unit.
Push
4
13
2
Photo 1
Figure 3
Front panel
Set screws
Airflow adjustment plate
OC112--1.qxp 11/16/98 4:46 PM Page 14

15
OPERATION PROCEDURE PHOTOS & ILLUSTRATIONS
3. REMOVING THE INDOOR MICRO CONTROLLER BOARD
AND INDOOR POWER BOARD
(1) Remove the front panel (Refer to (2)).
(1) Remove the electrical box cover (screw 4 ✕10)
(Refer to the photo 2).
INDOOR MICRO CONTROLLER BOARD
(1) Disconnect the following connectors on the indoor micro
controller board.
(connector in front of)
●CN60, CN51, CN3, CN29, CN21
●CN42, CN41, CN20
(2) Pull out the indoor micro controller board toward you, then
disconnect the rest of connectors.
●CN-53-M, CN35-M (See the photo 3)
INDOOR POWER BOARD
(1) Disconnect the following connectors on the indoor power
board.
●FAN1, CN-53-P, CN35-P
(2) Remove the screws of the indoor power board, then pull out
the indoor power board toward you. (See the photo 3)
Photo 2 Electrical parts box cover
Screw caps
Electrical parts box
Photo 3 Indoor micro controller board
Indoor power
board
Indoor power
board
4. REMOVING THE ELECTRICAL PARTS BOX
(1) Remove the front panel (Refer to (2))
(2) Remove the electrical parts box cover.
(3) Pull the nozzle assemble toward you as opening the catch
of the nozzle assemble.
(4) Disconnect the indoor/outdoor connector.
(5) Disconnect the following connector on the indoor micro con
troller board. (See the photo 4)
●CN60, CN5V, CN33, CN29, CN21, CN20
(6) Remove the connector FAN1 on the indoor power board.
(7) Disconnect the ground wire.
(8) Pull the disconnected lead wire out from the electrical parts
box.
(9) Push up the upper fixture catch to remove the box, then pull
the lower fixture and remove it from the box fixture.
Photo 4 Indoor malti
controller board fixture (uppre)
Indoor power
board
fixture (Lower)
Ground wire set screw Electrical parts box
Electrical parts box
OC112--1.qxp 11/16/98 4:46 PM Page 15

16
OPERATION PROCEDURE PHOTOS & ILLUSTRATIONS
5. REMOVING THE NOZZLE ASSEMBLE
(1) Remove the front panel (Refer to (2)).
(2) Remove the electrical parts box cover.
(3) Disconnect the connector (CN5V) on the indoor micro con
troller board.
(4) After unhook the right side of the corner box, press the
upper left side and remove the corner box.
(5) Remove the nozzle assemble from the fixture.
(See the photo 5)
(6) Remove the drain hose.
Photo 5
Heat exchanger Electrical parts box
fixture
Drain hose
6. REMOVING THE LINEFLOW FAN AND THE FAN MOTOR
(1) Remove the front panel (Refer to (2)).
(2) Remove the nozzle assembling (Refer to (5)).
(3) Remove the electrical parts box.
(4) Remove the fixture while pressing the right side of motor fix
ture catch (See the photo 6).
(5) Remove the left side of the motor fixture.
(6) Loosen the screw that fixes the line flow fan to the fan
motor, then remove the fan motor by sliding it to the right
side.
(See the photo 6)
(7) Pull the left-hand side of the heat exchanger toward you.
(See the photo 7)
(8) Remove the lineflow fan.
Photo 6 Heat exchanger Fan motor
Photo 7 Heat exchanger
7. REMOVING THE VANE MOTOR
(1) Remove the front panel.
(2) Remove the screw of the electrical parts box cover, and
remove the cover.
(3) Remove the screw of the vane motor, and remove the motor
from the shaft.
(4) Disconnect the vane motor connector (CN5V) on the indoor
controller board.
Photo 8
Heat exchanger
Vane motor
Nozzle assemble
8. REMOVING THE LIQUID PIPE THERMISTOR AND GAS
PIPE THERMISTOR
(1) Remove the front panel (Refer to (2)).
(2) Remove the electrical box cover.
(3) Remove the pipe cover.
(4) Cut the wiring fixed band.
(5) Remove the liquid pipe thermistor and gas pipe thermistor.
(See the photo 9)
(6) Disconnect the connector (N29) (CN21) on the indoor micro
controller board.
Photo 9
Heat exchanger
Drain hose
fixture set screw
set screws Drain hose
Nozzle assemble
fixture (left)
Nozzle assemble
fixture
Line flow fan
Heat exchanger
fixture (left)
Vane motor connect screw
Liquid pipe thermis-
tor
Gas pipe thermistor
Electrical parts box
fixture (right)
OC112--1.qxp 11/16/98 4:46 PM Page 16

17
PARTS LIST
8
PKFY-20VAM PANEL PARTS
PKFY-25VAM
1
2
3
4
5
6
7
8
9
10
R01 22A 651
R01 22A 691
—
R01 22A 500
R01 22A 635
T7W A00 658
R01 22A 808
R01 22A 096
R01 22A 054
—
FRONT PANEL
INTAKE GRILLE
RECEVING COVER
AIR FILTER
BOX
CONER BOX
BACK PLATE
SCREW CAP
CATCH
BRAND LABEL
No. Parts No. Parts Name Specifications PKFY-20VAM
PKFY-25VAM
Remarks
(Drawing No.)
Wiring
Diagram
Symbol
Recom-
mended
Q'ty
Unit Amount
Q'ty / set Price
1
1
1
1
1
1
1
1
1
1
(DT25C174H03)
(BC79R798H01)
OC112--1.qxp 11/16/98 4:47 PM Page 17

18
PKFY-20VAM ELECTRICAL PARTS
PKFY-25VAM
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
R01 22A 530
R01 22A 002
R01 22A 527
T7W A00 762
R01 22A 105
R01 22A 102
R01 005 103
T7W B02 310
T7W B02 313
—
T7W A10 716
T7W A11 716
R01 06A 202
R01 22A 202
R01 22A 223
R01 22A 114
T7W 520 239
T7W B01 294
R01 22A 126
T7W A00 202
T7W B00 713
T7W A00 305
—
NOZZLE ASSEMBLY
AUTO VANE
DRAIN HOSE
FAN MOTOR
RUBBER MOUNT
BEARING MOUNT
SLEEVE BEARING
I
NDOOR CONTROLLER BOARD
POWER BOARD
ELECTRICAL BOX
TERMINAL BLOCK
TERMINAL BLOCK
ROOM TEMPERATURE THERMISTOR
LIQUID PIPE THERMISTOR
VANE MOTOR
LINEFLOW FAN
FUSE
ADDRESS BOARD
MOTOR BAND
GAS PIPE THERMISTOR
REMOTE CONTROLLER
COARD REMOCON
CONTROLLER COVER
RC4V17-AA
2P (
M1, M2 )
3P ( L, N, ; )
250V 6.3A
No.
Parts No. Parts Name Specifications PKFY-20VAM
PKFY-25VAM
Remarks
(Drawing No.)
Wiring
Diagram
Symbol
Recom-
mended
Q'ty Unit Amount
Q'ty / set Price
MF1
M.B
P.B
TB2
TB5
TH21
TH22
TH23
R.B
10M
1
1
1
1
2
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
(BG00N801B01)
(BG00G828G04)
FILTER
CHECK MODE
TEST RUN
22
21
20
OC112--1.qxp 11/16/98 4:47 PM Page 18

19
PKFY-20VAM HEAT EXCHANGER PARTS
PKFY-25VAM
1
1
1
1
1
1
1
2
3
R01 22A 480
R01 23A 480
R01 22A 470
R01 22A 401
HEAT EXCHANGER
CONNECT PIPE
LINEAR EXPANSION VALVE
No. Parts No. Parts Name Specifications PKFY- PKFY-
20VAM 25VAM Remarks
(Drawing No.)
Wiring
Diagram
Symbol
Recom-
mended
Q'ty
Unit Amount
Q'ty / set Price
LEV
OC112--1.qxp 11/16/98 4:48 PM Page 19

CCopyright 1997 MITSUBISHI ELECTRIC ENGINEERING CO.,LTD.
Issued in Nov. 1998. No. OC112 251
Issued in Mar. 1997. No. OC112 1600
Printed in Japan
HEAD OFFICE MITSUBISHI DENKI BLDG.MARUNOUCHI TOKYO100-8310 TELEX J24532 CABLE MELCO TOKYO
New publication, effective Nov. 1998
Specifications subject to change without notice
OC112--1.qxp 11/16/98 4:48 PM Page 20