Piping Length: Vrv Dx And Hydrobox; Piping Length: Vrv Dx And Ra Dx - Daikin VRV IV+ RYYQ12U7Y1B Series Installer And User Manual

Example 1.3: unit 8: i≤40 m
However, extension is possible if all below conditions are met. In this
case limitation can be extended up to 90 m.
1
a b c d e f
2
A B C D E
h i j k l
3
1 2 3 4 5
1 Outdoor units
2 Refnet joints (A~G)
3 Indoor unit (1~8)
Conditions:
a The piping length between all indoor units to the nearest branch
kit is ≤40 m.
Example: h, i, j ... p≤40 m
b It is necessary to increase the pipe size of the gas and liquid
piping if the pipe length between the first branch kit and the
farthest indoor unit is over 40 m.
If the increased pipe size is larger than the pipe size of the main
pipe, then the pipe size of the main pipe has to be increased as
well.
Increase the pipe size as follows:
9.5 → 12.7; 12.7 → 15.9; 15.9 → 19.1; 19.1 → 22.2; 22.2 →
(a) (a)
25.4 ; 28.6 → 31.8 ; 34.9 → 38.1
(a) If the size-up size is NOT available, you must use the
standard size. Sizes bigger than the size-up size are NOT
allowed. But even if you use the standard size, you can
increase the maximum allowable length after the first branch if
all other conditions are met.
Example: unit 8: b+c+d+e+f+g+p≤90 m and b+c+d+e+f
+g>40 m; increase the pipe size of b, c, d, e, f, g.
c When the piping size is increased (step b), the piping length
has to be counted as double (except for the main pipe and the
pipes that are not increased in pipe size).
The total piping length has to be within limitations (see table
above).
Example: a+b×2+c×2+d×2+e×2+f×2+g×2+h+i+j+k+l+m+n
+p≤1000 m (500 m).
d The piping length difference between the nearest indoor unit
(from first branch) to the outdoor unit and the farthest indoor
unit to the outdoor unit is ≤40 m.
Example: The farthest indoor unit 8. The nearest indoor unit 1
→ (a+b+c+d+e+f+g+p)–(a+h)≤40 m.
5.3.6

Piping length: VRV DX and Hydrobox

For system containing VRV DX indoor units and Hydrobox:
System setup
Example
Example 1
a b c d e f g
A B C D E F
h i j k l m
1 2 3 4 5 6
Example 2
i
a
A
b
H1
c d e f g
1 2 3 4 5
RYYQ+RYMQ+RXYQ8~20U7Y1B
VRV IV+ heat pump
4P546228-1 – 2018.09
g
F G
p
H1
m n
6 7
8
H2
(a)
Description
Branch with refnet joint
H1
G
p
n
7
8
H2
Branch with refnet joint
and refnet header
B
k
j
7 8
H2
h
6
Example
Example 3
a
b c d e f g h
1 2 3 4 5 6 7
H2
1~7 VRV DX indoor units
8 Hydrobox unit (HXY080/125)
Maximum allowable length
Between outdoor and indoor units.
Actual piping 135 m
length
Example 1:
▪ a+b+c+d+e+f+g+p≤135 m
▪ a+b+c+d+k≤135 m
Example 2:
▪ a+i+k≤135 m
▪ a+b+e≤135 m
Example 3:
▪ a+i≤135 m
▪ a+d≤135 m
(a)
Equivalent length 160 m
Total piping length 300 m
Example 3:
▪ a+b+c+d+e+f+g+h+i≤300 m
(a) Assume equivalent piping length of refnet joint=0.5 m and
refnet header=1 m (for calculation purposes).
Maximum allowable height difference (on Hydrobox indoor unit)
H1 ≤50 m (40 m) (if outdoor is located below indoor units)
H2 ≤15 m
Maximum allowable length after branch
The pipe length from the first refrigerant branch kit to the indoor unit
≤40 m.
Example 1: unit 8: b+c+d+e+f+g+p≤40 m
Example 2: unit 6: b+h≤40 m, unit 8: i+k≤40 m
Example 3: unit 8: i≤40 m, unit 2: c≤40 m
5.3.7

Piping length: VRV DX and RA DX

For system containing VRV DX indoor units and RA DX indoor units:
System setup
a
A
c
H4
e
BP1
H5
H1
1 2
Header
BP box
1~5 RA DX indoor units
5 Preparation
Description
Branch with refnet
header
H1
i
8
b d
B
f g
6 7
BP2
k
3
H2
H6
l
4
5
Installer and user reference guide
17