14 Piping installation
Installation and operation manual
20
REYQ8~20+REMQ5U7Y1B
VRV IV+ heat recovery
4P546222-1B – 2020.10
Indoor unit capacity index
3 pipes
290≤x<640
KHRQ23M64H
(a)
≥640
KHRQ23M75H
(a)
If the pipe size above the refnet header is Ø34.9 or more,
KHRQ23M75H is required.
INFORMATION
Maximum 8 branches can be connected to a header.
▪ How to choose an outdoor multi connection piping kit. Choose
from the following table in accordance with the number of outdoor
units.
Number of outdoor units
Branch kit name
2
BHFQ23P907
3
BHFQ23P1357
INFORMATION
Reducers or T-joints are field supplied.
NOTICE
Refrigerant branch kits can only be used with R410A.
14.1.4
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
b
a
Pattern 2
b
a
a
b
a
b
b
aa
a
To indoor unit
b
Piping between outdoor units
NOT allowed (oil remains in piping)
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
b
a
b
a
b
a
a
a
≥200 mm
a
To indoor unit
b
Oil collects to the outmost outdoor unit when the system
stops
NOT allowed (oil remains in piping)
Allowed
▪ If the piping length between the outdoor units exceeds 2 m, create
a rise of 200 mm or more in the suction gas line and the high
pressure/low pressure gas line within a length of 2 m from the kit.
If
Then
≤2 m
a
b
≤2 m
>2 m
a
≤2 m
≤2 m
≥200 mm
≥200 mm
b
>2 m
>2 m
a
To indoor unit
b
Piping between outdoor units
NOTICE
There are restrictions on the refrigerant pipe connection
order between outdoor units during installation in case of a
multiple outdoor unit system. Install according to following
restrictions. The capacities of outdoor units A, B and C
must fulfill the following restriction conditions: A≥B≥C.
A
B
C
a b
c
a
To indoor units
b
Outdoor unit multi connecting piping kit (first branch)
c
Outdoor unit multi connecting piping kit (second branch)
14.2
Connecting the refrigerant piping
14.2.1
To route the refrigerant piping
Installation of refrigerant piping is possible as front connection or
side connection (when taken out from the bottom) as shown in the
figure below.
a
b
c
a
Left-side connection
Summary of Contents for REYQ8U7Y1B
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