Multiple Outdoor Units: Possible Layouts - Daikin VRV IV+ RYYQ12U7Y1B Series Installer And User Manual

5 Preparation
6,7 VRV DX indoor units
Maximum allowable length
▪ Between outdoor unit and indoor unit.
Actual piping 100 m
length
Example:
a+b+g+l≤100 m
(a)
Equivalent length 120 m
Total piping length 250 m
Example:
a+b+d+g+l+k+c+e+f+h+i+j≤250 m
(a) Assume equivalent piping length of refnet joint=0.5 m and
refnet header=1 m (for calculation purposes).
▪ Between BP unit and indoor unit.
Indoor unit capacity index
<60
60
71
Remark: Minimum allowable length between outdoor unit and first
refrigerant branch kit>5 m (the refrigerant noise from the outdoor unit
can be transmitted).
Example: a>5 m
Maximum allowable height difference
H1 ≤50 m (40 m) (if outdoor is located below indoor units)
H2 ≤15 m
H4 ≤40 m
H5 ≤15 m
H6 ≤5 m
Maximum allowable length after branch
The pipe length from the first refrigerant branch kit to the indoor unit
≤50 m.
Example: b+g+l≤50 m
If the piping length between the first branch and BP unit or VRV DX
indoor unit is over 20 m, it is necessary to increase the gas and
liquid piping size between the first branch and BP unit or VRV DX
indoor unit. If the piping diameter of the sized up piping exceeds the
diameter of the piping before the first branch kit, than the latter also
requires a liquid piping and gas piping size up.
5.3.8

Multiple outdoor units: Possible layouts

▪ The piping between the outdoor units must be routed level or
slightly upward to avoid the risk of oil retention into the piping.
Pattern 1
a
b
a
b
a
b
a To indoor unit
b Piping between outdoor units
X Not allowed (oil remains in piping)
Installer and user reference guide
18
Pipe length
2~15 m
2~12 m
2~8 m
Pattern 2
a
b
a
b
a a
b
O Allowed
▪ To avoid the risk of oil retention to the outmost outdoor unit,
always connect the stop valve and the piping between outdoor
units as shown in the 4 correct possibilities of the figure below.
a
b b b
a
b b b
a
a
b
b
a
a
a To indoor unit
b Oil collects to the outmost outdoor unit when the system
stops
X Not allowed
O Allowed
▪ If the piping length between the outdoor units exceeds 2 m, create
a rise of 200 mm or more in the gas line within a length of 2 m
from the kit.
If
≤2 m
a
>2 m
a
≤2 m
a To indoor unit
b Piping between outdoor units
a
b
a
Then
b
≤2 m
>2 m >2 m
b
≤2 m
RYYQ+RYMQ+RXYQ8~20U7Y1B
VRV IV+ heat pump
4P546228-1 – 2018.09