3-7. Insulating the Refrigerant Tubing
Tubing Insulation
● Standard selection of insulation material
Under the environment of the high temperature and
high humidity, the surface of the insulation material
is easy to become condensation. This will result in
leakage and dew drop. Refer to the chart shown below
when selecting the insulation material. In case that
the ambient temperature and relative humidity are
placed above the line of the insulation thickness, the
condensation may occasionally make a dew drop on
the surface of the insulation material. In this case,
select the better insulation efficiency.
* However, since the condition will be different
due to the sort of the insulation material and the
environmental condition of the installation place, see
the chart shown below as a reference when making
a selection.
Standard selection of tubing insulation
Sort of insulation material
Upper limits of usage
temperature
Calculating condition
Thermal conductivity
of insulation material
Refrigerant temperature
o6.35
100
90
80
70
60
50
40
10
20
30
Ambient temperature [°C]
o15.88
100
90
80
70
60
50
40
10
20
30
Ambient temperature [°C]
o25.4
100
90
80
70
60
50
40
10
20
30
Ambient temperature [°C]
Polyethylene heat resisting
material
Gas tubing : 120 °C or above
Other tubing : 80 °C or above
0.043 W/(m · K)
(Average temperature 23 °C)
2 °C
o9.52
100
Thickness
90
30mm
Thickness
80
20mm
70
Thickness
60
10mm
50
40
40
50
10
20
Ambient temperature [°C]
o19.05
100
90
Thickness
30mm
80
Thickness
20mm
70
60
Thickness
10mm
50
40
40
50
10
20
Ambient temperature [°C]
o28.58
100
90
Thickness
30mm
80
Thickness
70
20mm
60
Thickness
10mm
50
40
40
50
10
20
Ambient temperature [°C]
EN - 19
Thermal insulation
(120°C or higher heat resistance)
Control cable
Gas tube
3WAY Multi 3-tube Side
Duct (or similar)
Discharge tube
tape
(mid-size tube)
Thermal insulation
o12.7
100
90
Thickness
30mm
80
Thickness
20mm
70
Thickness
60
10mm
50
40
30
40
50
10
o22.22
100
90
Thickness
80
30mm
Thickness
20mm
70
60
Thickness
10mm
50
40
30
40
50
10
o31.75
100
90
Thickness
30mm
80
Thickness
70
20mm
60
Thickness
50
10mm
40
30
40
50
10
Duct (or similar) tape
(for waterproofing)
Thermal insulation
Liquid tube
Suction tube
(largest tube)
Liquid tube (small tube)
Fig. 18
Thickness
30mm
Thickness
20mm
Thickness
10mm
20
30
40
50
Ambient temperature [°C]
Thickness
30mm
Thickness
20mm
Thickness
10mm
20
30
40
50
Ambient temperature [°C]
Thickness
30mm
Thickness
20mm
Thickness
10mm
20
30
40
50
Ambient temperature [°C]