Mitsubishi Electric Mr.Slim PK36FK, Technical & Service Manual

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5. ADVANCED MICROPROCESSOR
(1) Easy to Use Microprocessor
1) Ultra-Thin Remote Controller
The streamlined, square 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) Atrractive Liquid Crystal Display (LCD)
Units operation mode, set temperature, room temperature, timer setting,
fan speed, louver operation, 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 you set. Once the timer is set, the remaining time is shown on the
LCD.
4) Self-Diagnostic Feature Indicates Faults 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 memorized 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 troublefree. Remote controller
wire can be extended up to 550 yards.
(3) Automatic Cooling / Heating Changeover Operation
An automatic cooling and heating changeover operation system is provided to ensure easy control and year-round air
conditioning.
Once the desired temperature is set, unit operation is switched automatically between cooling and heating, in
accordance with the room temperatures. In addition, the use of outdoor unit fan speed controller enables cooling opera-
tion at outdoor.
6. REDI-CHARGED REFRIGERANT SYSTEM
PRE-CHARGE REFRIGERANT REQUIRED FOR MAXIMUM PIPING LENGTH 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 or 25ft minimum. 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.
With normal circulation systems, a high-pressure refrigerant, condensed for cooling by the outdoor heat exacanger, is
reduced in pressure by capillary tubes in the indoor unit after passing through the restrictor valve in the outdoor unit (see
Figure 1). With the new circulation system, the direction of the restrictor valve is reversed as shown in Figure 2, and the
condensed high pressure refrigerant is reduced in pressure by the capacity tubes in the outdoor unit. This results in a “two-
phase refrigerant” of reduced pressure in the liquid section of the piping, The density of this two-phase refrigerant is 1/3~
1/2 of that of the high pressure liquid refrigerant, and thus is required in smaller amounts (see Figures 1 and 2). As a result,
the length of the piping can be extended further, and the effects of height differences are reduced. These new circulation
system are also equipped with a large accumulator which allows the refrigerant required for the 100ft piping length to be
enclosed in the outdoor unit. The result is an air conditioner that requires no charging unless piping is extended beyond
100ft.
Indoor unit Outdoor unit
Indoor
heat
exchanger
4•way
valve
Accumulator
Compressor
Outdoor
heat
exchanger
Capillary tubes
for heating
Capillary
tubes for
cooling
Liquid section
of piping
HIgh-pressure
liquid
retrigerant
Restrictor
valve
Restrictor valve
Indoor unit Outdoor unit
Indoor
heat
exchanger
4•way
valve
Accumulator
Compressor
Outdoor
heat
exchanger
Capillary tubes
for cooling
Capillary
tubes for
heating
Liquid section
of piping
Low-pressure
two-phase
retrigerant
Restrictor
valve
Restrictor valve
MITSUBISHI ELECTRIC
ON
DRY
COOL FAN
CHECK
SET TEMP
TIMER OFF
AUTO STOP
AUTO START
F
HR
F
LOW HIGH
AUTO RETURN
CHECK TEST RUN
POWER
ON/OFF
MODE SELECT
SET
TEMPERATURE
FAN COOL/DRY
COOLER WARMER
TIMER MODE HOURS
FAN SPEED LOW/HIOGH
AIR
DISCHARGE
UP/DOWN
SWING
STOP
CHECK TEST RUN
•CENTRALLY CONTROLLED•
Fig.1
Normal Refrigerant Circulation System.
New Refrigerant Circulation System.
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