General Instructions On The Installation Of Refrigerant Pipes; Preparing Copper Refrigeration Pipes - Hitachi UTOPIA R32 Series Installation And Operation Manual

!
CAUTION
• Secure the fixed connection with a suitable wrench and use a torque wrench to tighten the flare
nut on the threaded connections.
• Do not exceed the torque value indicated in the table. The fitting can become misshapen and the
connection may leak.
If temperature and humidity inside the ceiling exceed 27°C / RH 80%, dew condensation occurs on
the surface of the accessory insulation. Wrap additional insulation (approx. 5 ~ 10mm thickness)
around the accessory insulation of the refrigerant pipe as a preventive measure.
For buried pipe with joints such as an elbow or a socket, provide service access doors to facilitate
the check for connection.
The pipes must be reinforced by an earthquake resistant support so that they will not be damaged
by an external force.
Do not clamp the refrigerant pipe tightly when supporting them for prevention of heat stress.
When connecting indoor/outdoor units with refrigerant pipes, fix the pipes as required so that the
pipes may not to contact weak portions of the wall, ceiling, etc. Failure to take this measure may
lead to an abnormal sound caused by the vibration of the pipe.
Perform the air tight test according to Installation and Operation Manual of the outdoor unit.
After connecting the refrigerant piping, seal the open space between knockout hole and refrigerant
pipes by using insulation material.
Unit side

5.4 General instructions on the installation of refrigerant pipes

5.4.1 Preparing copper refrigeration pipes
Clean the area where the copper refrigeration pipe preparation work is to be carried out. It must
particularly be free of waste, soil, wood or metal shavings and, in general, any substance that could
enter the ends of the pipe during handling. The copper pipe must be clean and have no remains of
adhesive, cement, dust or other substances adhered to it.
!
CAUTION
• Before you install the pipes, blow the inside with oxygen-free nitrogen gas to eliminate any
remains of dust or other substances.
PMEN0654 rev.0 - 12/2023
N° Description
Insulation material

Insulation material

Field supplied

Insulation material

5
17