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
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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.
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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
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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]
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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
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