Hitachi CH-Box Installation Manual page 24

(2) Piping Work for CH-Box
Refer to Technical Catalogue and Installation Manual of the outdoor unit for the piping diameter and
the installation condition.
(3) Selecting Piping Size
● Select the size for the high/low pressure gas pipe,
low pressure gas pipe and liquid pipe according
to Table 5.1. The size depends on the indoor unit
total capacity connected downstream of the
CH-Box.
● As for the multi-kit branch or header branch, refer
to the Technical Catalog for the Outdoor Unit.
● Perform the piping connection work for the CH-Box
as shown below.
(a) Outdoor Unit Side Field Piping Size
Connected
Indoor Unit Capacity: Q
kW
< 16.0
16.0 ≤ Q < 25.0
25.0 ≤ Q < 33.5
33.5 ≤ Q < 45.0
45.0 ≤ Q < 50.0
50.0 ≤ Q < 61.5
61.5 ≤ Q < 73.0
73.0 ≤ Q ≤ 85.0
NOTE:
Refer to "Position of Piping Connection" for the details of the piping connection for the CH-Box.
Use field-supplied reducer in case the field piping and CH-Box piping connection does not match.
14
Table 5.1 Outdoor Unit Side Field Piping Size
Low Pressure
Gas Pipe (A)
mm (inch)
f15.88 (5/8)
f19.05 (3/4)
f22.2 (7/8)
f25.4 (1)
f28.58 (1-1/8)
f28.58 (1-1/8)
f28.58 (1-1/8)
f31.75 (1-1/4)
(a) Outdoor Unit Connecting Side
High/Low Pressure
Gas Pipe (B)
(Field-Supplied)
Low Pressure
Gas Pipe (A)
(Field-Supplied)
Liquid Pipe (C)
(Field-Supplied)
Gas Pipe (D)
(Field-Supplied)
Liquid Pipe (E)
(Field-Supplied)
(b) Indoor Unit Connecting Side
High/Low Pressure
Gas Pipe (B)
mm (inch)
f12.7 (1/2)
f15.88 (5/8)
f19.05 (3/4)
f22.2 (7/8)
f22.2 (7/8)
f22.2 (7/8)
f25.4 (1)
f28.58 (1-1/8)
Liquid Pipe (C)
mm (inch)
f9.52 (3/8)
f9.52 (3/8)
f9.52 (3/8)
f12.7 (1/2)
f12.7 (1/2)
f15.88 (5/8)
f15.88 (5/8)
f19.05 (3/4)
P5417025-rev.1