1
Appendex- 1
Allowable length of refrigerant pipes and allowable height
difference between units
a
b
c
d
e
(e)
(b)
(a)
(c)
(d)
L4
f
g
h
i
j
(j)
L5
L6
Height
difference
between
outdoor
units
H3
≤ 5 m
Height
difference
between
outdoor
and indoor
units:
H1
≤ (70 m)
Main
piping
L1
Outdoor
Equivalent length corresponded to farthest piping
between outdoor unit
LO
< 40 m
Y-shape branching
joint for gas pipe
Branching piping
L2
Equivalent length corresponded to farthest piping
L
≤ 250 m
Equivalent length corresponded to farthest piping after 1st branching
Li
≤ 90 m
Height
difference
between
indoor
units:
H2
≤ 40 m
Indoor unit
Connecting piping of indoor unit
1st branching
section
Branching
header
Indoor unit
Y-joint
L7
Y-joint
Y-shape branching
joint for liquid pipe
A
Header
unit
B
Follower
C
Follower
D
Follower
E
Follower
unit
L3
Header unit
A
Header unit
A
Follower unit
B
Follower unit
B
Follower unit
C
Follower unit
C
Main pipe
Main pipe
To the indoor unit
To the indoor unit
Incorrect
Figure 1
Figure 2
t
c
e
r
r
o
c
n
I
t
c
e
r
r
o
C
System restriction
s
t
i
n
u
5
o
t
p
U
n
o
i
t
a
n
i
b
m
o
c
t
i
n
u
r
o
o
d
t
u
O
P
H
0
2
1
o
t
p
U
s
t
i
n
u
r
o
o
d
t
u
o
f
o
y
t
i
c
a
p
a
c
l
a
t
o
T
s
t
i
n
u
8
2
1
o
t
p
U
n
o
i
t
c
e
n
n
o
c
t
i
n
u
r
o
o
d
n
I
Total capacity of indoor units
(varies depending on the height difference between
indoor units.)
H2 ≤ 15 m
Single
200% of outdoor units’ capacity
Combination
150% of outdoor units’ capacity
H2 > 15 m
105% of outdoor units’ capacity
