Hitachi RAS-18FSXN - Refrigerant Charge

Figure 1: two branches on the main pipe
Figure 2: capacity ratio of the indoor units ≤ 40%
A
B
41 - 90 m
41 - 90 m
A
20%
80%
A: main branch
B: secondary branch
A: main branch
Figure 3: distributor used as branching for three pipes and
branching for two pipes
Figure 4: do not connect a branch to a distributor
A
B
≤ 40 m
≤ 40 m
CH
CH
CH
CH
CH CH
B
A
A
CH
A: branch
B: distributor
A: branch
B: distributor
3.1.8 Refrigerant charge
¿ Installation airtight test
Check that
the stop valves are fully closed; to do so, remove the covers and check that the valves are closed to the
corresponding torque:
• Heat pump system: Details of the gas and liquid stop valves, see on page 44.
• Heat recovery system: Details of the gas and liquid stop valves, see on page 52.
Check that the outdoor and indoor units are connected via the field-supplied refrigerant pipes.
3 Piping work and
refrigerant charge
58
SMGB0065 rev. 1 - 12/2010