82
Pipe insulation
Insulating the refrigerant pipes and branch joints
f Check for gas leakage before completing (the hose and pipe insulation) and if there is no sign of leakage, make sure to
insulate the pipes and hoses.
f Use EPDM material insulator that meets the following conditions.
Test item Unit Standard
Density g/cm
3
0.048~0.096
Dimensional change rate by heat % Below -5
Absorption rate g/cm
3
Below 0.005
Thermal conduction rate W/m·K Below 0.037
Moisture transpiration factor ng/(m
2
·s·Pa) Below 15
Moisture transpiration grade g/(m
2
·24h) Below 15
Formaldehyde dispersion mg/L There should be none
Oxygen rate % Over 25
Selecting the refrigerant pipe insulator
f Insulate the gas pipe and liquid pipe by referring to the thickness of insulator for each pipe size.
f The standard condition is; temperature at 30°C, humidity less than 85%. If case if the humidity is higher, you must
increase the size by one grade as stated in below table.
Pipe
Diameter of
refrigerant pipe
Insulator (CoolingHeating)
Remarks
General
[30 °C, 85 %]
High humidity
[30 °C, over 85 %]
EPDM,NBR
Liquid pipe
Ø 6.35~Ø 9.52 9 mm
Heat resisting
temperature over 120°C
Ø 12.7~Ø 50.80 13 mm
Gas pipe
Ø 6.35 13 mm 19 mm
Ø 9.52 ~ Ø 25.40
19 mm
25 mm
Ø 28.58 ~ Ø 44.45 32 mm
Ø 50.80 25 mm 38 mm
❇ When installing insulation in places and conditions below, use the same insulation that is used for high humidity
conditions.
<Geological condition>
- High humidity places such as shoreline, hot spring, near lake or river, and ridge (when the part of the building is
covered by earth and sand.)
<Operation purpose condition>
- Restaurant ceiling, sauna, swimming pool etc.
<Building construction condition>
- The ceiling frequently exposed to moisture and cooling is not covered. (e.g. The pipe installed at a corridor of a
dormitory and studio or near an exit that opens and closes frequently.”)
- The place where the pipe is installed is highly humid due to the lack of ventilation system.