The pipe thickness of the refrigerant piping shall comply with the
applicable legislation. The minimal pipe thickness for R410A
piping must be in accordance with the table below.
Pipe
Ø
6.4
9.5
12.7
15.9
19.1
22.2
28.6
34.9
In case the required pipe sizes (inch sizes) are not available, it is
also allowed to use other diameters (mm sizes), taken the
following into account:
select the pipe size nearest to the required size.
use the suitable adapters for the change-over from inch to
mm pipes (field supply).
9.3. Selection of refrigerant branch kits
Refrigerant refnets
When using refnet joints at the first branch counted from the
outdoor unit side, choose from the following table in accordance
with the capacity of the outdoor unit (example: refnet joint a)
Outdoor unit
capacity type (Hp)
10
KHRQ23M29T
12~16
KHRQ23M64T
For refnets joints other than the first branch (example refnet
joint b and c), select the proper branch kit model based on the
total capacity index of all indoor units connected after the
refrigerant branch.
Indoor unit
capacity index
<200
KHRQ23M20T
200≤x<290
KHRQ23M29T
290≤x<640
KHRQ23M64T
640≥
KHRQ23M75T
Concerning refnet headers, choose from the following table in
accordance with the total capacity of all the indoor units
connected below the refnet header:
Indoor unit
capacity index
<200
KHRQ23M29H
200≤x<290
KHRQ23M29H
290≤x<640
KHRQ23M64H
640≥
KHRQ23M75H
NOTICE
Refrigerant branch kits can only be used with R410A.
REYAQ10~16P7Y1B
VRVIII system outdoor unit
4PW62582-1A – 08.2011
Minimal thickness t (mm)
0.80
0.80
0.80
0.99
0.80
0.80
0.99
1.21
Refrigerant branch kit name
3 pipes
2 pipes
KHRQ22M29T
KHRQ22M64T
Refrigerant branch kit name
3 pipes
2 pipes
KHRQ22M20T
KHRQ22M29T
KHRQ22M64T
KHRQ22M75T
Refrigerant branch kit name
3 pipes
2 pipes
KHRQ22M29H
KHRQ22M29H
KHRQ22M64H
KHRQ22M75H
9.4. System piping limitations
Piping length restrictions
Make sure to perform the piping installation within the range of the
maximum allowable pipe length, allowable level difference and
allowable length after branching as indicated below ("8"=HXHD125):
Example 1: Branch with refnet joint
a
b
c
d
e
A
B
C
D
h
i
j
k
BS
BS
BS
BS
q
r
s
t
1
2
3
4
Example 2: Branch with refnet joint and refnet header
a
A
b
H1
c
d
e
BS
BS
BS
BS
n
p
q
r
1
2
3
4
Example 3: Branch with refnet header
a
b
c
d
e
f
BS
BS
BS
BS
BS
j
k
m
n
p
1
2
3
4
5
Maximum allowable lengths
Actual pipe length between outdoor and indoor unit ≤100 m
Example 1: a+b+c+d+e+f+g+p≤100 m a+b+c+d+k+t≤100 m
Example 2: a+i+k≤100 m
Example 3: a+i≤100 m
Equivalent piping length between indoor and outdoor unit ≤120 m
equivalent pipe length of refnet to be taken 0.5 m and for header
1.0 m.
Equivalent pipe length of BSVQ100 = 4 m
Equivalent pipe length of BSVQ160 = 4 m
Equivalent pipe length of BSVQ250 = 6 m
Total piping length from outdoor to all indoor units ≤300 m
Pipe length from first branch kit (either refnet joint or refnet header) to
indoor unit ≤40 m
[Example 1]: unit 8: b+c+d+e+f+g+p≤40 m
[Example 2]: unit 6: b+h+t≤40 m, unit 8: i+k≤40 m
[Example 3]: unit 8: i≤40 m, unit 2: c+k≤40 m
g
f
H1
E
F
G
p
l
m
n
BS
BS
BS
u
v
w
5
6
7 H2
8
i
B
k
j
BS
8
m
g
f
h
H2
BS
BS
7
s
t
5
6
H1
g
h
i
BS
BS
q
r
6
7
H2
8
a+b+e+q≤100 m
a+d+m≤100 m
Installation manual
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