Technical Changes - Mitsubishi Electric SUZ-KA25VA2 Technical & Service Manual

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TECHNICAL CHANGES

INFORMATION FOR THE AIR CONDITIONER WITH R410A REFRIGERANT
• This room air conditioner adopts an HFC refrigerant (R410A) which never destroys the ozone layer.
• Pay particular attention to the following points, though the basic installation procedure is same as that for R22 conditioners.
1 As R410A has working pressure approximate 1.6 times as high as that of R22, some special tools and piping parts/
materials are required. Refer to the table below.
2 Take sufficient care not to allow water and other contaminations to enter the R410A refrigerant during storage and
installation, since it is more susceptible to contaminations than R22.
3 For refrigerant piping, use clean, pressure-proof parts/materials specifically designed for R410A. (Refer to 2. Refrigerant
piping.)
4 Composition change may occur in R410A since it is a mixed refrigerant. When charging, charge liquid refrigerant to prevent
composition change.
Refrigerant
Composition (Ratio)
Refrigerant handling
Chlorine
Safety group (ASHRAE)
Molecular weight
Boiling point ( )
Steam pressure [25 ](Mpa)
Saturated steam density [25 ](Kg/
Combustibility
ODP 1
GWP 2
Refrigerant charge method
Additional charge on leakage
Kind
Color
Smell
1: Ozone Depletion Potential
2: Global Warming Potential
New Specification
The incompatible refrigerant oil easily separates from
refrigerant and is in the upper layer inside the suction muffler.
Raising position of the oil back hole enables to back the
refrigerant oil of the upper layer to flow back to the
compressor.
Compressor
NOTE : The unit of pressure has been changed to MPa on the international system of units (SI unit system).
The conversion factor is: 1 (MPa [Gauge]) =10.2 (kgf/cm
OCH472A
New refrigerant
HFC-32: HFC-125 (50%:50%)
Pseudo-azeotropic refrigerant
Not included
)
Non combustible
From liquid phase in cylinder
Incompatible oil
: based on CFC-11
: based on CO
2
Suction muffler
Oil back hole
Refrigerant oil
Refrigerant
3
R410A
A1/A1
72.6
-51.4
1.557
64
0
1730
Possible
None
None
Current Specification
Since refrigerant and refrigerant oil are compatible with
each other, refrigerant oil backs to the compressor through
the lower position oil back hole.
Compressor
[Gauge])
2
Previous refrigerant
R22
R22 (100%)
Single refrigerant
Included
A1
86.5
-40.8
0.94
44.4
Non combustible
0.055
1700
Gas phase
Possible
Compatible oil
Light yellow
None
Suction muffler
Oil back hole
Refrigerant oil /Refrigerant