7.Precautions for Laying Refrigerant Piping
Cautions on pipe handling
1) Protect the open end of the pipe against dust and moisture.
2) All pipe bends should be as gentle as possible. Use a pipe bender for bending.(Bending radius should be 30 to 40mm or larger.)
Selection of copper and heat insulation materials
When using commercial copper pipes and fittings, observe the following :
1) Insulation material: Polyethylene foam
Heat transfer rate: 0.041 to 0.052W/mK(0.035to 0.045kcal/mh
o
C)
Refrigerant gas pipe's surface temperature reaches 110
o
C max.
Choose heat insulation materials that will withstand this temperature.
2) Be sure to insulate both the gas and liquid piping and to provide insulation dimensions as below.
Check the type of refrigerant to be used on the machine nameplate.
Precautions when adding R32
Fill from the liquid pipe in liquid form.(recommend)
1) Before filling, check whether the cylinder has a siphon attached or not.(It should have something like "liquid filling siphon attached"
displayed on it.) (recommend)
2) Be sure to use the R32 tools to ensure pressure and to prevent foreign objects entering.
1) This system must use
refrigerant
R32.
2) Add refrigerant 20g per meter when the total piping length
exceeds the standard value, but make sure that the total liquid
piping length should be less than the max. value.
Filling a cylinder with an attached siphon
Stand the cylinder upright when filling.
There is a siphon pipe inside, so the
cylinder need not be upside-down
to fill with liquid.
Filling other cylinders
Turn the cylinder upside-down
when filing.
24
5. Refilling the refrigerant
6. Charging with refrigerant
Gas pipe
Gas pipe insulation
O.D.:9.52mm,12.7mm
Thickness:0.8mm
I.D.:12-15mm
Th
i
ckness:13mm m
i
n.
Liquid pipe
Liquid pipe insulation
O.D.:6.35mm
Thickness:0.8mm
I.D.:8-1
0
mm
Th
i
ckness:1
0
mm m
i
n.
30m
50m
40m
70m
4U71S2PR1FA
4U80S2PR1FA
3U55S2PR1FA
50
m
100
m
5U125S2PN1FA
4
0
m
8
0
m
5U100S2PS1FA
