Pipe Connection; Refrigerant Charge Amount - Hitachi RWM-(H)FSN3E Technical Catalogue

9 Piping work and
refrigerant charge

9.2.2 Pipe connection

Cover the end of the pipe appropriately when it is to be inserted
through holes in walls and roofs, etc.
Keep the ends of the pipes covered while other installation work is
being carried out to avoid the entry of dampness or dirt.
Do not place the pipes directly on the ground without appropriate
protection or adhesive vinyl tape to cover the ends.
Where the pipe installation is not completed for a certain amount of
time, braze the ends of the pipe to seal. Then fill it with oxygen-free
nitrogen gas through a Schrader valve to avoid the accumulation of
humidity and/or contamination through dirt.
N O T E
• Where polyethylene foam insulation is used, a 10 mm thick layer should be used for the liquid pipe and bet-
ween 15 and 20 mm for the gas pipe.
• Install the insulation after the pipe surface temperature has dropped to the same temperature as that of the
room, otherwise the insulation may melt.
Do not use insulating material that contains NH
cause leaks.
Where the installer has supplied his own branches, these should be appropriately insulated to avoid decreases in capacity
in line with to environmental conditions and dew on the surface of the piping due to low pressure.

9.3 Refrigerant charge amount

Refrigerant for 30 m of piping length has been charged into the outdoor units.
N O T E
For YUTAKI S series, the maximum piping length is 30 m, so it is not required an additional refrigerant charge.

Refrigerant charge before shipment (W
114
TCGB0070 rev.3 - 04/2012
(ammonium), as it could damage the copper in the pipe and subsequently
3
(kg))
0
Outdoor unit model
RAS-2HVRN2
RAS-3HVRNME-AF
RAS-4H(V)RNME-AF
RAS-(5/6)H(V)RNME-AF
RAS-8HRNME-AF
RAS-10HRNME-AF
W (kg)
0
1.6
2.4
3.9
4.0
7.3
7.8