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Service Procedures
3
SM830063
7. Cautions for New Refrigerant R407C
1
Care regarding piping
1-1. There is no need to change piping and tube wall thickness. Use refrigerant pipes of the same wall
thickness as R22.
1-2. Prevent impurities including water, dust and oxide from coming into the pipe.
Impurities can cause R407C refrigerant deterioration and compressor defects.
Due to the different features of the refrigerant and refrigerating machine oil, the prevention of water
and other impurities becomes more important than ever.
2
Make sure to refill the refrigerant in liquid form.
2-1. Since R407C is a non-azeotrope, refilling the refrigerant in gas form can lower performance and
cause defects of the unit.
2-2. Since refrigerant composition changes and performance decreases when gas leaks, collect the
remaining refrigerant and refill the required total amount of new refrigerant after fixing the leak.
3
Different tools
3-1. Tools specs have been changed due to the features of R407C.
Some of the R22 tools cannot be used.
Copper tube
Type
0
1/2 H, H
Outer diameter
ø6.35
ø9.52
ø12.7
ø15.88 ø19.05
ø22.2
ø25.4
ø28.58
Wall thickness
0.8
0.8
0.8
1.0
1.0
1.2
1.0
1.0
* C1220 type with JIS H 3300 designation (Copper Pipe and Copper Alloy Seamless Pipe)
New
tools
Yes
Yes
Yes
Yes
Yes
R22 tools
compatible
with R407C
No
No
Yes
No
No
Remarks
Types of refrigerant and refrigerating machine oil, and
pressure gauge are different.
To resist pressure and oil, material has been changed.
Use a conventional vacuum pump if it is equipped with a
check valve. If it has no check valve, purchase and attach
a vacuum pump adaptor.
Leak detectors for CFC and HCFC which react to chlorine
do not function because R407C contains no chlorine.
Leak detector for R407C can be used for HFC134a.
Mineral oil (for example, suniso oil) can be used as R22
oil. Use synthetic fluid (for example, ether oil) as R407C
oil.
Product name
Gauge
manifold
Charge hose
Vacuum pump
Leak detector
Flaring oil
* Using both R22 tools and new tools together can cause defects.
Vacuum pump
Gauge manifold
1202_C_I
Single-outlet valve
(with siphon tube)
Liquid refrigerant can
be refilled standing it
up straight.
Valve
Liquid
1171_M_I
Outlet
Inlet
1203_C_I
3-2. Ues a R407C exclusive cylinder only.