Hitachi RAS-18FSXNS2E - Pipe Connection

25
PMML0628 rev.0 - 05/2023
3
PIPE CONNECTION
PIPING WORK AND REFRIGERANT CHARGE
◆ Example 2: Using piping connecon kit
Outdoor
Unit
A
Outdoor
Unit
B
Indoor
Unit
Indoor
Unit
First Branch
Mul-Kit
Piping Connecon Kit
d
e
f
g
h
A B
3.3 Pipe connecon
Cover the end of the pipe appropriately when needs to be inserted through holes in walls and
roofs, etc.
Keep the ends of the pipes covered while other installaon work is being carried out to avoid the
entry of dampness or dirt.
Do not place the pipes directly on the ground without appropriate protecon or adhesive vinyl
tape to cover the ends.
Where the pipe installaon is not completed for a certain amount of me, braze the ends of
the pipe to seal. Then ll it with oxygen-free nitrogen gas through a Schrader valve to avoid the
accumulaon of humidity and/or contaminaon through dirt.
 NOTE
• Where polyethylene foam insulaon is used, a 10mm thick layer should be used for the liquid
pipe and between 15 and 20 mm for the gas pipe.
• Install the insulaon aer the pipe surface temperature has dropped to the same temperature
as that of the room, otherwise the insulaon may melt.
Do not use insulang material that contains NH
3
(ammonium), as it could damage the copper in
the pipe and subsequently cause leaks.
Where the lter has supplied his own branches, these should be appropriately insulated to avoid
decreases in capacity in line with environmental condions and dew on the surface of the piping
due to low pressure.