Installation Manual

En-12
5. PIPE INSTALLATION
5.1. Refrigerant pipe size and allowable piping length
CAUTION
Do not mix with other air/gases except the specifi ed refrigerant for the refrigerant cycle. Ventilate the area if there is a
refrigerant leak while performing the installation.
Over-tightening when connecting the fl are fi ttings can result in cracking or breaking of the fl are nuts, and thus cause a
refrigerant leak.
For on-site piping insulation, be sure that the insulation covers the entire unit’s pipe connection. Pipe exposure can lead to
water leaks from condensation and consequently cause burn injury from contact.
During fl are connection, apply the refrigeration compressor oil (or equivalent) used for the outdoor unit to the fl are section.
Secure the piping by taping it or performing pipe pinching so that impurities, water or dust do not penetrate inside the
piping.
H1
a
b
c
d
e
f
h
g
i
k
j
l
m
H2
H3
H
4
Separation Tube
Outdoor
Unit
Indoor
Unit1
Branch BoxBranch Box
Branch Box
(Primary)
(Secondary1)
(Secondary2)
Indoor
Unit2
Indoor
Unit3
Indoor
Unit4
Indoor
Unit5
Indoor
Unit6
Indoor
Unit7
Indoor
Unit8
Limitation
m (ft)
Diagram
Allowable pipe length
(actual pipe length)
Maximum total equivalent pipe length 115 or less (377) Total
Between outdoor unit and the farthest indoor unit 70 or less (230) a + b + c + m
Between outdoor unit and branch boxes 55 or less (180) a + b + c + d + e
Between branch box and indoor unit
Total 60 or less (197) f + g + h + i + j + k + l + m
Each unit Between 3-15 (10-49) f, g, h, i, j, k, l, m
Between outdoor unit and the first separation tube 5 or more (16) a
Between outdoor unit and branch box
(when there is no separation tube)
5 or more (16) a+d
Allowable
height
difference
Between outdoor unit and indoor unit 30 or less (98) H1
Between outdoor unit and branch box 30 or less (98) H2
Between branch box and branch box 15 or less (49) H3
Between indoor unit and indoor unit 15 or less (49) H4
Note) Install the separation tube close to the branch box. Keep the pipe length for sections c, d, and e as short as possible.
Pipe size selection
Code
Condition
(model code of indoor unit)
Gas pipe
[mm (in.)]
Liquid pipe
[mm (in.)]
From the outdoor unit to the fi rst separation tube a — Ø 15.88 (5/8) Ø 9.52 (3/8)
From the separation tube to the next separation tube b — Ø 15.88 (5/8) Ø 9.52 (3/8)
From the separation tube to the branch box c, d, e — Ø 15.88 (5/8) Ø 9.52 (3/8)
From the branch box to the indoor unit
f, g, h, i,
j, k, l, m
7, 9, 12 Ø 9.52 (3/8)
Ø 6.35 (1/4)18 Ø 12.70 (1/2)
24 Ø 15.88 (5/8)
9380120001-06 EN.indd 129380120001-06 EN.indd 12 6/16/2558 BE 8:20 PM6/16/2558 BE 8:20 PM