Mitsubishi Electric PK12FK3 User manual

OC274-1
CONTENTS
1. TECHNICAL CHANGE···················································································OC274- 2
2. FEATURES·····································································································OC274- 3
3. PART NAMES AND FUNCTIONS··································································OC274- 6
4. SPECIFICATIONS ··························································································OC274- 8
5. DATA···············································································································OC274- 9
6. OUTLINES AND DIMENSIONS ·····································································OC274-17
7. REFRIGERANT SYSTEM DIAGRAM····························································OC274-20
8. WIRING DIAGRAM·························································································OC274-21
9. OPERATION FLOW-CHART··········································································OC274-23
10.MICROPROCESSOR CONTROL····································································OC274-26
11. TROUBLESHOOTING····················································································OC274-38
12. SYSTEM CONTROL·······················································································OC274-44
13. DISASSEMBLY PROCEDURE·······································································OC274-49
14. PARTS LIST····································································································OC274-52
15. OPTIONAL PARTS·························································································OC274-58
PK12FK3
PK18FK3
PK24FK3
PK30FK3
PK36FK3
OC274--1.qxp 1.12.14 5:30 PM Page 1

OC274-2
1TECHNICAL CHANGE
PK12FK1➔PK12FK3
PK18FK2➔PK18FK3
PK24FK2➔PK24FK3
PK30FK2➔PK30FK3
PK36FK2➔PK36FK3
●INDOOR CONTROLLER BOARD has changed.
1) From TRANSFORMER to POWER BOARD.
2) From JUMPER CONNECTOR(J1) to DIP SWITCH(SW1).
3) From JUMPER CONNECTOR(J5) to DIP SWITCH(SW5).
4) The number of switches of SW7 changed from 4 to 3 pieces.
5) SW8 for option and SW9 for model selector are added.
OC274--1.qxp 1.12.14 5:30 PM Page 2

OC274-3
FEATURES
2
1. COMPACT DESIGN
The PK series models have been downsized and now require such minimal wall space that they can even be installed
above windows. For the PK12FK3, 11-13/16in of wall space between the ceiling and the window allows “above window”
installation. (13-3/8in for the PK24/30/36FK3)
2. AUTO FLAP SHUTTER
With a simple flick of the OFF switch the air outlet will be closed off with a shutter. The shutter also functions as a flap
during operation to adjust the air flow angle, with “Auto Angle 1” securing a comfortable air flow.
3. INSTALLATION : FAST AND ENDLESSLY ADAPTABLE
(1) Multi-directional piping
Multi directional drain and refrigerant piping radically improves flexibility in selecting installation layouts.
PK12FK3 drain piping can be installed in 5 directions, while PK18/24/30/36FK3 models boast refrigerant piping in 4
directions and drain piping 2 directions.
(2) Back plate installation guide
The back plate installation guide gives clear instructions on installation positions. The enlarged back plate secures the
unit firmly to the wall, while the support piece which lifts the unit makes left side piping work much easier.
(3) Easily removable filter
The presence of thumbscrews on the filters means that the filters can be quickly and smoothly removed.
FILTER
CHECK MODE
TEST RUN
TIMER OFF TIMER
CHECK SET TEMP.
CLOCK AUTO AUTO
START STOP
SWING
FAN
SPEED AUTO
RETURN
Indoor unit Remote controller
Models Cooling capacity SEER
PK12FK3 12,500 Btu/h 11.5
PK18FK3 18,500 Btu/h 11.3
PK24FK3 24,000 Btu/h 10.6
PK30FK3 30,000 Btu/h 10.7
PK36FK3 34,200 Btu/h 10.2
OC274--1.qxp 1.12.14 5:30 PM Page 3

OC274-4
4. ADVANCED MICROPROCESSOR
(1) Easy to Use Microprocessor
1) Ultra-Thin Remote Controller
The streamlined, wide controller is designed to
blend with any kind of interior and the adoption of
a sophisticated microprocessor allows you to
carry out a wide range of operations easily.
2) Attractive Liquid Crystal Display (LCD)
Units operation mode, set temperature, room tem-
perature, timer setting, fan speed,
and air flow direction are displayed on the
remote controller with the easily understood visual
Liquid Crystal Display (LCD).
3) Convenient 24-Hour ON-OFF Timer
The timer allows Mr.SLIM to be switched on or
off automatically at the time is shown on the LCD.
4) Self-Diagnostic Feature Indicates Instantly
In the rare case when a problem occurs, the unit stops operating and the set temperature indicator changes to the
self-diagnostic indicator, indicating the location of the fault.
If the check switch is pressed twice, the unit stops operating and the check mode is initiated. The cause of the most
recent problem stored in the memory is displayed on the LCD. This is extremely useful for maintenance purposes.
5) Useful Memory Feature for Storing Instructions
The previous set value is memorised so that constant temperature control can be obtained. This is convenient when,
for example, a power failure occurs.
(2) Non-polar Two-Wire Remote Controller Cables
The non-polar, two-wire type remote controller cable is slim, installation is simple and trouble-free. Remote controller
wire can be extended up to 550 yards.
5. REDI-CHARGED REFRIGERANT SYSTEM
PRE-CHARGE REFRIGERANT REQUIRED FOR LINE LENGTH OF 100ft AT
SHIPMENT. PREVENTING TROUBLES DUE TO SHORTAGE OF REFRIGERANT.
The unique refrigerant circuit and a large accumulator always controls the refrigerant to its optimum condition regardless of
the length of 164ft maximum. The additional refrigerant charging work at the field which often caused uncertain problems
heretofore is completely eliminated. This unique system serves to improve the quality of work and reliability, and also helps
to speed up the installation work.
TIMER OFF TIMER
CHECK SET TEMP.
DRY COOL
FAN
CLOCK AUTO AUTO
START STOP
MODE TIMER ON/OFF CLOCK/TIMER FAN SPEED AIR DISCHARGE FILTER
CHECK
TEST RUN
AIR SWEEP
SET TEMP. TIMER SET
F
FAN
SPEED
SWING
AUTO
RETURN
REMOTE CONTROLLER
[Remote controller]
OC274--1.qxp 1.12.14 5:30 PM Page 4

OC274-5
6. HIGH RELIABILITY AND EASY SERVICING
In addition to the self-diagnostic function, units are also equipped with a 3-minute time delay mechanism (cooling), an auto
restart function, an emergency operation function, a test run switch, etc., to assure high reliability and easy servicing.
7. FOUR-WAY PIPING ACCESS MAKES
INSTALLATION LAYOUT EASY
Piping on the outdoor unit may be connected from either of
four directions: front, rear, side or beneath the base.
This easy-access design makes it possible to install a
number of units in a compact arrangement at a single site.
The outdoor unit allows for unheard-of flexibility in
determining a piping layout, thus greatly simplifying
installation.
8. FRONT-ACCESS FACILITATES
MAINTENANCE
The outdoor unit has been designed with a front access
service panel that allows easy access to all maintenance
point, regardless of the installation layout. What’s more, this
front panel may be removed by loosening only two screws.
It all adds up to greatly simplified maintenance work.
9. NITROGEN GAS IS CHARGED TO
INDOOR UNIT
Indoor unit and refrigerant pipes are charged with nitrogen
gas (N2) instead of R-22 before shipment from the
factory.
Rear
Right
Base
Front
OC274--1.qxp 1.12.14 5:30 PM Page 5

OC274-6
3 PART NAMES AND FUNCTIONS
Remote controller operation buttons
TIMER OFF TIMER
CHECK SET TEMP.
DRY COOL
FAN
CLOCK AUTO AUTO
START STOP
MODE TIMER ON/OFF CLOCK/TIMER FAN SPEED AIR DISCHARGE FILTER
CHECK
TEST RUN
AIR SWEEP
SET TEMP. TIMER SET
F
FAN
SPEED
SWING
AUTO
RETURN
REMOTE CONTROLLER
FILTER button
This resets the filter service indica-
tion display.
TIMER ON/OFF button
This switches between continuous
operation and the timer operation.
SET TEMPERATURE
button
This sets the room temperature.
The temperature setting can be per-
formed in 2˚F units.
Setting range :
Cooling 65˚F to 87˚F
CHECK-TEST RUN button
Only press this button to perform an
inspection check or test operation.
Do not use it for normal operation.
AIR SWEEP button
This switches the horizontal fan
motion ON and OFF.
(This button is not available)
CLOCK/TIMER button
This sets or switches the current
time,start time and stop time.
FAN SPEED button
This sets the ventilation fan speed.
AIR DISCHARGE
button
This adjusts the vertical angle of the
ventilation.
ON/OFF button
This switches between the opera-
tion and stop modes each time it is
press. The lamp on this button
lights during operation.
OPERATION MODE
button
Press this button to switch the cool-
ing,electronic dry (Dehumidify), fan
modes.
Remote controller
Settings remain in effect until changed.
Air conditioner can be operated by simply pushing ON/OFF button once settings have been made.
OC274--1.qxp 1.12.14 5:30 PM Page 6

OC274-7
TIMER OFF TIMER
CHECK SET TEMP.
DRY COOL
FAN
CLOCK AUTO AUTO
START STOP
MODE TIMER ON/OFF CLOCK/TIMER FAN SPEED AIR DISCHARGE FILTER
CHECK
TEST RUN
AIR SWEEP
SET TEMP. TIMER SET
F
FAN
SPEED
SWING
AUTO
RETURN
REMOTE CONTROLLER
Operation lamp
This lamp lights during operation,
goes off when the unit stops and
flashes when a malfunction occurs.
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 continuous
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.
CHECK display
This indicates when a malfunction
has occurred in the unit which should
be checked.
display
This lamp lights when electricity is
supplied to the unit.
display
This displays the selected setting
temperature.
CLOCK display
The current time , start time and stop
time can be displayed in ten second
intervals by pressing the time switch
button. The start time or stop time is
always displayed during the timer
operation.
AIR DISCHARGE display
This displays the air direction.
display
The temperature of the return air is
displayed during operation. The dis-
play range is 47° to 97°F. The dis-
play flashes 47°F when the actual
temperature is less than 47° and
flashes 97°F when the actual tem-
perature is greater than 97°F.
In this display example on the bottom left, a condi-
tion where all display lamps light is shown for
explanation purposes although this differs from
actual operation.
display
This display lights in the check mode
or when a test operation is per-
formed.
CHECK MODE
TEST RUN
display
This lamp lights when the filter needs
to be cleaned.
FAN SPEED display
The selected fan speed is displayed.
Caution
●Only the display lights when the unit is stopped and power supplied to the unit.
●When power is turned ON for the first time the (CENTRAL CTRL) display appears to go off momentarily but this is not a malfunction.
●When the central control remote control unit, which is sold separately, is used the ON-OFF button,OPERATION MODE button and SET
TEMP button do not operate.
●“NOTAVAILABLE” is displayed when the AIR SWEEP button are pressed.
(AIR SWEEP function is not provided for PK series.)
FILTER
Remote controller display
OC274--1.qxp 1.12.14 5:30 PM Page 7

OC274-8
4 SPECIFICATIONS
MODELS : PK12FK3, PK18FK3, PK24FK3, PK30FK3, PK36FK3
Capacity
Power consumption
EER
SEER
INDOOR UNIT MODEL
External finish
Power supply
Max. fuse size (time delay)
Min ampacity
Fan motor
Airflow Hi-Lo
Moisture removal
Sound level Hi-Lo
Cond. drain connection OD
Dimensions
Weight
OUTDOOR UNIT MODEL
External finish
Power supply
Max. fuse size (time delay)
Min. ampacity
Fan motor
Compressor
Crankcase heater
Refrigerant control
Sound level
Dimensions
Weight
REMOTE CONTROLLER
Control voltage (by built-in transformer)
REFRIGERANT PIPING
Pipe size
Connection method
Between the indoor
& outdoor units
❈1
❈1
❈1
Dry
Wet
W
D
H
Model
W
D
H
Liquid
Gas
Indoors
Outdoors
Height
Piping length
Btu/h
kW
V, Phase, Hz
A
A
F.L.A.
CFM
CFM
Pints/h
dB
in.
in.
in.
in.
Ib.
V, Phase, Hz
A
A
F.L.A
R.L.A
L.R.A
A(W)
dB
in.
in.
in.
Ib.
in.
in.
ft
fr
PK12FK3
Model
12,500
1.21
10.3
11.5
PK12FK3
15
1
0.7
490-350
440-320
3.8
45-38
1
49-7/32
7-7/8
11-13/16
37
PU12EK1
15
11
0.65
RH167NAB
8.9
29
0.11/0.12 (23/28)
50
25-9/16
105
130
130
PK18FK3
18,500
1.75
10.6
11.3
PK18FK3
15
1
0.7
710-530
640-480
5.3
48-41
1
53
PU18EK1
20
16
0.75
RH247NAB
12.0
37
0.11/0.12 (23/28)
53
33-1/2
154
3/8
5/8
55-1/8
34-1/4
11-5/8
PK24FK3
24,000
2.34
10.3
10.6
PK24FK3
Munsell 3.4Y7.7/0.8
115, 1, 60
15
1
0.7
710-530
640-480
7.2
48-41
1
9-1/4
13-3/8
53
PU24EK1
Munsell 5Y7/1
208/230, 1, 60
20
16
0.65+0.65
NH33NBD
11.5
54
0.16/0.17 (33/39)
Capillary tube
55
207
With indoor unit
Indoor unit - remote controller : DC12V, Indoor unit - outdoor unit : DC12V
Not supplied (optional parts)
Flared
Flared
PK30FK3
30,000
3.06
9.8
10.7
PK30FK3
15
2
1.0
990-780
890-700
9.6
49-44
1
62
PU30EK1
30
20
0.65+0.65
NH41NAD
14.0
73
0.16/0.17 (33/39)
55
49-9/16
208
164
164
1/2
3/4
PK36FK3
34,200
3.47
9.9
10.2
PK36FK3
15
2
1.0
990-780
890-700
10.5
49-44
1
62
PU36EK1
30
22
0.75+0.75
NH47NAD
17.5
87
0.16/0.17 (33/39)
55
38-3/16
13-9/16
220
66-5/32
Item
NOTES : ❈1.Rating conditions —indoor : DB 80˚F, WB 67˚F outdoor : DB 95˚F, WB 75˚F.
Operating range
Indoor intake air temperature
DB 95˚F, WB 71˚F
DB 67˚F, WB 57˚F
Outdoor intake air temperature
DB 115˚F
DB 0˚F *
Cooling Maximum
Minimum
*In case of the wind baffle is installed.
(In case of the wind baffle is not installed, the minimum temperature will be DB 23˚F.)
OC274--1.qxp 1.12.14 5:30 PM Page 8

OC274-9
DATA
5
Notes 1. B.F. : Bypass Factor, IWB : Intake air wet-bulb temperature
TC : Total Capacity (x103 Btu/h), SHC : Sensible Heat Capacity (x103 Btu/h)
TPC : Total Power Consumption (kW)
2. Cooling capacity correction factors and Refrigerant piping length (one way) range.
MODEL Refrigerant piping length (one way)
PK12FK3
PK18FK3
PK24FK3
PK30FK3
PK36FK3
1.0
1.0
1.0
1.0
1.0
25ft
0.992
0.992
0.981
0.981
0.981
40ft
0.983
0.983
0.968
0.968
0.968
55ft
0.978
0.978
0.952
0.952
0.952
70ft
0.966
0.966
0.940
0.940
0.940
85ft
0.959
0.959
0.925
0.925
0.925
100ft
0.950
0.950
0.913
0.913
0.913
115ft
0.945
0.945
0.900
0.900
0.900
130ft
—
—
0.886
0.886
0.886
150ft
—
—
0.874
0.874
0.874
164ft
TC
14.5
13.6
12.7
12.6
12.0
11.8
21.5
20.1
18.8
18.6
17.8
17.4
27.9
26.1
24.3
24.1
23.0
22.6
34.9
32.6
30.4
30.2
28.8
28.3
39.8
37.1
34.7
34.4
32.8
32.2
IWB
(˚F)
71
67
63
62.5
60
59
71
67
63
62.5
60
59
71
67
63
62.5
60
59
71
67
63
62.5
60
59
71
67
63
62.5
60
59
Indoor air
Airflow
(CFM)
B.F
Models
PK12FK3
PK18FK3
PK24FK3
PK30FK3
PK36FK3
490
0.18
710
0.14
710
0.14
990
0.15
990
0.15
DB 80˚F
DB75˚F(50%RH)
DB72˚F(50%RH)
DB70˚F(50%RH)
DB 80˚F
DB75˚F(50%RH)
DB72˚F(50%RH)
DB70˚F(50%RH)
DB 80˚F
DB75˚F(50%RH)
DB72˚F(50%RH)
DB70˚F(50%RH)
DB 80˚F
DB75˚F(50%RH)
DB72˚F(50%RH)
DB70˚F(50%RH)
DB 80˚F
DB75˚F(50%RH)
DB72˚F(50%RH)
DB70˚F(50%RH)
75
SHC
9.8
11.0
12.0
10.7
10.4
10.1
14.8
16.5
17.9
16.0
15.6
15.0
16.4
18.8
20.7
18.3
17.8
17.3
21.5
24.5
26.9
23.8
23.2
22.5
23.0
26.3
29.3
25.8
25.1
24.3
TPC
1.05
1.03
1.01
1.01
0.99
0.99
1.52
1.49
1.46
1.45
1.43
1.43
2.04
1.99
1.95
1.94
1.92
1.91
2.66
2.61
2.55
2.54
2.51
2.49
3.02
2.96
2.89
2.88
2.84
2.83
TC
14.0
13.1
12.2
12.1
11.5
11.3
20.8
19.3
18.0
17.9
17.1
16.7
26.9
25.1
23.4
23.2
22.1
21.7
33.7
31.4
29.2
29.0
27.7
27.1
38.4
35.7
33.3
33.1
31.5
30.9
85
SHC
9.5
10.6
11.5
10.3
10.0
9.7
14.3
15.8
17.2
15.4
15.0
14.4
15.8
18.1
20.0
17.6
17.1
16.6
20.8
23.6
25.8
22.9
22.3
21.5
22.1
25.3
28.1
24.8
24.1
23.3
TPC
1.14
1.12
1.09
1.09
1.07
1.06
1.65
1.61
1.57
1.57
1.55
1.54
2.21
2.16
2.11
2.10
2.07
2.05
2.89
2.82
2.75
2.75
2.70
2.69
3.28
3.20
3.12
3.11
3.07
3.05
TC
13.5
12.5
11.6
11.5
11.0
10.8
19.9
18.5
17.2
17.1
16.3
16.0
25.8
24.0
22.4
22.2
21.1
20.7
32.3
30.0
27.9
27.7
26.4
25.9
36.8
34.2
31.9
31.6
30.1
29.5
Outdoor intake air DB temperature(˚F)
95
SHC
9.1
10.1
10.9
9.8
9.5
9.2
13.7
15.2
16.4
14.7
14.3
13.8
15.1
17.3
19.1
16.8
16.4
15.8
19.9
22.5
24.6
21.9
21.3
20.6
21.2
24.3
26.9
23.7
23.0
22.3
TPC
1.24
1.21
1.18
1.17
1.15
1.15
1.80
1.75
1.70
1.70
1.67
1.66
2.40
2.34
2.28
2.27
2.23
2.22
3.14
3.06
2.98
2.97
2.92
2.90
3.57
3.47
3.38
3.37
3.31
3.29
TC
12.8
11.9
11.1
11.0
10.4
10.2
19.0
17.6
16.4
16.2
15.5
15.1
24.6
22.9
21.3
21.1
20.0
19.6
30.8
28.6
26.6
26.3
25.1
24.6
35.1
32.6
30.3
30.0
28.6
28.0
105
SHC
8.7
9.6
10.5
9.3
9.0
8.7
13.0
14.4
15.6
13.9
13.6
13.1
14.4
16.5
18.2
16.0
15.5
15.0
19.0
21.5
23.5
20.7
20.2
19.5
20.2
23.1
25.6
22.5
21.9
21.1
TPC
1.35
1.31
1.27
1.26
1.24
1.23
1.95
1.89
1.83
1.83
1.79
1.78
2.61
2.53
2.45
2.44
2.40
2.38
3.41
3.30
3.21
3.20
3.14
3.11
3.87
3.74
3.64
3.63
3.56
3.53
TC
12.2
11.3
10.5
10.4
9.9
9.7
18.1
16.7
15.5
15.4
14.6
14.3
23.4
21.7
20.1
19.9
18.9
18.5
29.3
27.1
25.1
24.9
23.7
23.2
33.4
30.9
28.7
28.4
27.0
26.4
115
SHC
8.3
9.2
9.9
8.8
8.6
8.3
12.4
13.7
14.8
13.2
12.8
12.4
13.7
15.6
17.2
15.1
14.7
14.1
18.1
20.3
22.2
19.6
19.1
18.4
19.3
21.9
24.2
21.3
20.7
19.9
TPC
1.45
1.40
1.36
1.35
1.32
1.31
2.10
2.03
1.96
1.96
1.92
1.90
2.81
2.71
2.62
2.62
2.56
2.54
3.68
3.54
3.43
3.42
3.35
3.32
4.17
4.02
3.89
3.88
3.80
3.77
1. PERFORMANCE DATA
1) COOLING CAPACITY
2) COOLING CAPACITY CORRECTIONS
OC274--1.qxp 1.12.14 5:30 PM Page 9

OC274-10
2. PERFORMANCE CURVE
NOTE : A point on the curve shows the reference point.
PK12FK3 COOLING CAPACITY PK18FK3 COOLING CAPACITY
PK24FK3 COOLING CAPACITY PK30FK3 COOLING CAPACITY
18
71
67
63
71
67
63
12
6
1.6
1.4
1.2
1.0
0.8
023 3235 45 55 65(67) 75 85 95 105 115
Total capacity (✕103Btu/h)Total power consumption (kW)
Outdoor intake air DB temperature (°F)
indoor intake air WB temperature (°F)
indoor intake air WB temperature (°F)
SHF=0.81
30
71
67
63
71
67
63
18
24
12
3.0
2.5
2.0
1.5
1.0
023 3235 45 55 65(67) 75 85 95 105 115
Total capacity (✕103Btu/h)Total power consumption (kW)
Outdoor intake air DB temperature (°F)
indoor intake air WB temperature (°F)
indoor intake air WB temperature (°F)
SHF=0.82
Total capacity (✕103Btu/h)Total power consumption (kW)
Outdoor intake air DB temperature (°F)
023 3235 45 65 (67) 75 85 95 105 11555
1.5
2.0
2.5
3.0
3.5
18
36
24
30
71
67
63
71
67
63
023 3235 45 65 (67) 75 85 95 105 11555
2.0
2.5
3.0
3.5
4.0
24
42
30
36
71
67
63
71
67
63
indoor intake air WB temperature (°F)
indoor intake air WB temperature (°F)
Total capacity (✕103Btu/h)Total power consumption (kW)
Outdoor intake air DB temperature (°F)
indoor intake air WB temperature (°F)
indoor intake air WB temperature (°F)
SHF=0.72 SHF=0.72
OC274--1.qxp 1.12.14 5:30 PM Page 10