Twin And Triple System Installation - Hitachi RAS-5HVRNM1E Service Manual

3 Piping work and
refrigerant charge

3.4.4 Twin and triple system installation

Height difference between indoor units and distributor
Install all indoor units at the same height. When a height difference is unavoidable between the indoor units due to the
construction of the building, it should always be less than H
the indoor units, but never higher.
Example: Twin system
1. Indoor unit
2. Indoor unit
3. Branch pipe
A. Height difference between two indoors smaller than H
B. Smaller than H (m)
in
Maximum height between
indoor units
HVRN(1)S(E)
Installing distributor
1 Install the distributor supplied by HITACHI on request. A tee can not be installed instead of a branch pipe.
Example: Twin system
2 Installing the distributor. Fix the branch pipe horizontally to the pillar, wall or ceiling. The piping must not be fixed rigidly
to the wall as thermal expansion and contraction can cause pipe fracture.
Example: Twin system
A
B
C
A. Horizontal.
B. To indoor unit.
C. To outdoor unit.
N O T E
Fix the piping from outside of insulation or inserting absorber between the pipe and a fixing metal.
78
SMGB0060 rev. 1- 12/2010
(m)
in
H (m)
in
0.5
A
A. Vertical.
B. To indoor unit.
Fix the branch pipe to the surface of
pillar or wall.
(m). Install the branch pipe at the same height or lower than
in
2
1
B
B
A. Horizontal.
Fixing the branch pipe to ceiling or
beam.
3
A