SiEN34-705
Appendix
General Information
133
7.3.1 Branch with Refnet Joint
Heat Pump 50Hz/60Hz, Cooling Only 50Hz (RX(Y)Q5~54P, 50PH)
(Connection of 8 indoor units Heat pump system)
Single outdoor
system
(RX(Y)Q5 ~ 18P)
Example refrigerant branch using REFNET joint
Multi outdoor
system
RX(Y)Q20P ~
RX(Y)Q16PH ~
a
A
B
C
D
E
F
G
b
c
d
e
f
g
h
i
j
k
l
m
n
1
2
3
4
5
6
7
8
H2
Outdoor unit
REFNET joint (C)
Indoor units (1-8)
H1
(
)
a
b
c
d
e
f
g
8
H2
H1
H3
p
h
i
j
k
l
m
n
1
2
3
4
5
6
7
A
B
C
D
E
F
G
REFNET joint (A-G)
First Outdoor
unit multi connection
piping kit
Outdoor unit
Indoor units ( 1 - 8 )
Maximum
allowable
length
Between outdoor (*2) and indoor units
• Actual pipe length
Pipe length between outdoor (*2) and indoor units
≤
165m
Example unit 8: a + b + c + d + e + f + g + p
≤
165m
• Equivalent length
Equivalent pipe length between outdoor (*2) and indoor units
≤
190m *(See Note 1)
(assume equivalent pipe length of refnet joint to be 0.5m, that of refnet header to be 1m,
calculation purposes)
• Total extension length
Total piping length from outdoor unit (*2) to all indoor units
≤
1000m
Between outdoor unit and Outdoor unit multi connection piping kit
(Only for multi system)
• Actual pipe length
Pipe length between outdoor unit and Outdoor unit multi
connection piping kit
≤
10m
• Equivalent length
Equivalent length between outdoor unit and Outdoor unit
multi connection piping kit
≤
13m
Allowable
height
length
Between outdoor and indoor units
• Difference in height
Difference in height between outdoor and indoor units (H1)
≤
50m
(
≤
90m if the outdoor unit is below)
Between indoor and indoor units
• Difference in height
Difference in height between adjacent indoor units (H2)
≤
15m
Between outdoor and outdoor units
• Difference in height
Difference in height between outdoor unit (H3)
≤
5m
Allowable
length after
the branch
• Actual pipe length
Pipe length from first refrigerant branch kit (either refnet joint or refnet header) to indoor unit
≤
40m
*(See Note 2)
Example unit 8: b + c + d + e + f + g + p
≤
40m *(See Note 2)
Refer Note 1 and Note 2 on page
143, 144.
*2 In case of multi outdoor system, re-read to the first Outdoor unit multi
connection piping kit as seen from the indoor unit.
r
t
s
r
≤
10m (E
qu
iv
a
lent length:
≤
1
3
m)
s
≤
10m (E
qu
iv
a
lent length:
≤
1
3
m)
t
≤
10m (E
qu
iv
a
lent length:
≤
1
3
m)
O
u
tdoor
u
nit
