SiEN34-705
Installation
General Information
35
3.2.4 Thermal Insulation Work (Refrigerant Piping)
!
Operational steps
Materials
The thermal insulation materials which are used must be well able to withstand the heat from
the pipes.
Example:
Heat pump type: Heat resistant polyethylene foam (heat resistance of at least 120°C)
Cooling only: Polyethylene foam (heat resistance of 100°C or more)
Essential Points
of Thermal
Insulation
The insulation of jointed areas such as the soldered, flared or flanged sections should only be
carried out after the successful completion of the air tight test.
The tips for insulation
!
Gas piping must be insulated.
!
Be sure to insulate the liquid-side and gas-side piping for the inter-unit piping and the
refrigerant branch kits and always use 18-type or better insulation for the oil pressure
equalizer.
!
Materials: Glass fiber or heat resistant polyethylene foam.
Thickness: 10mm or more
Heat resistance: Gas pipe : 120°C or more / Liquid pipe : 70°C or more
!
If you think the humidity around the cooling piping might exceed 30°C and RH80%, reinforce
the insulation on the cooling piping (at least 20mm thick). Condensation might form on the
surface of the insulation.
!
Insulation of both liquid and gas pipe
Caution
Be sure to size up the main gas line in the connecting piping of the suction gas piping if the
equivalent length of the piping between the indoor and outdoor units exceeds 90m. In order to
minimize the reduction of capacity caused by the pressure drop, the refrigerant pipe size may
be sized up.
Refrigerant pipe
work
Insulation
(jointed areas)
Insulation (with
the exception of
the jointed areas)
Air tight test
(V0985)
Insulator
Finishing tape
Gas pipe
Electric cable
Liquid pipe
