Features - Mitsubishi Mr.SLIM PUH18EK Technical & Service Manual

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FEATURES

1. REDI-CHARGED REFRIGERANT SYSTEM
The industry's first redi-charged refrigerant system.
There is no need to adjust the amount of refrigerant to match the piping length
on- site unless lines exceed 100ft.
You will see a major reduction in installation time and labor costs.
The unique refrigerant circuit and a large accumulator always control the refrigerant to its optimum condition unless the
pipe length exceeds 100ft. The additional refrigerant charging work in 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.
Figure 1. Normal Refrigerant Circulation System
Indoor unit
Indoor
heat
exchanger
Capillary
tubes for
Liquid section
cooling
of piping
Restrictor
HIgh-pressure
valve
liquid
refrigerant
With normal circulation systems, a high-pressure refrigerant, condensed for cooling by the outdoor heat exchanger, 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 capillary 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.
2. 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.
3. 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.
4. 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.
Outdoor unit
4•way
valve
Accumulator
Compressor
Capillary tubes
for heating
Restrictor valve
Figure 2. New Refrigerant Circulation System
Indoor unit
Indoor
heat
Outdoor
exchanger
heat
exchanger
Capillary
tubes for
heating
Restrictor
valve
Front
2
Outdoor unit
4•way
valve
Accumulator
Compressor
Capillary tubes
Liquid section
for cooling
of piping
Low-pressure
Restrictor valve
two-phase
refrigerant
Rear
Right
Base
Outdoor
heat
exchanger
HEATING
COOLING