4 Preparation
Installation and operation manual
9
REYQ8~20+REMQ5T7Y1B
VRV IV system air conditioner
4P353996-1E – 2018.04
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.
4.2.4 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
Pattern 2
a To indoor unit
b Piping between outdoor units
X Not allowed (oil remains in piping)
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 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 2m, 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 2m from the kit.
If Then
≤2m
>2m
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 To indoor units
b Outdoor unit multi connecting piping kit (first branch)
c Outdoor unit multi connecting piping kit (second branch)
4.3 Preparing electrical wiring
4.3.1 Safety device requirements
The power supply must be protected with the required safety
devices, i.e. a main switch, a slow blow fuse on each phase and an
earth leakage protector in accordance with the applicable legislation.
For standard combinations
Selection and sizing of the wiring should be done in accordance with
the applicable legislation based on the information mentioned in the
table below.
Non-continuous heating
Model Minimum
circuit
ampacity
Recommended
fuses
REMQ5 16.1A 20A
REYQ8 16.1A 20A
REYQ10 22.0A 25A