6 Installation
Installer and user reference guide
29
RWEYQ8~1 RWEYQ8~14T9Y1B
VRV IV water-cooled system air conditioner
4P452191-1 – 2017.04
NOTICE
The refrigerant charge of the system must be less than
100 kg. This means that in case the calculated total
refrigerant charge is equal to or more than 95 kg you must
divide your multiple outdoor system into smaller
independent systems, each containing less than 95 kg
refrigerant charge. For factory charge, refer to the unit
name plate.
In case of heat pump mode
Formula:
R=[(X
1
×
Ø22.2
)×0.37+(X
2
×
Ø19.1
)×0.26+(X
3
×
Ø15.9
)×0.18+
(X
4
×
Ø12.7
)×0.12+(X
5
×
Ø9.5
)×0.059+(X
6
×
Ø6.4
)×0.022]+A
R
Additional refrigerant to be charged [in kg and rounded off
to 1 decimal place]
X
1...6
Total length [m] of liquid piping size at
Øa
A
Parameter A
Parameter A.
If the total indoor unit capacity connection ratio
(CR)>100%, charge an additional 0.5 kg of refrigerant per outdoor
unit.
In case of heat recovery mode
Formula:
R=[(X
1
×
Ø22.2
)×0.37+(X
2
×
Ø19.1
)×0.26+(X
3
×
Ø15.9
)×0.18+
(X
4
×
Ø12.7
)×0.12+(X
5
×
Ø9.5
)×0.059+(X
6
×
Ø6.4
)×0.022]×1.04+A+C
R
Additional refrigerant to be charged [in kg and rounded off
to 1 decimal place]
X
1...6
Total length [m] of liquid piping size at
Øa
A
Parameter A
C
Parameter C
Parameter A.
If the total indoor unit capacity connection ratio
(CR)>100%, charge an additional 0.5 kg of refrigerant per outdoor
unit.
Parameter C.
When using more than one multi BS unit, add the sum
of the individual BS unit charge factors.
Model
C
BS1Q10
0.05 kg
BS1Q16
0.1 kg
BS1Q25
0.2 kg
BS4Q
0.3 kg
BS6Q
0.4 kg
BS8Q
0.5 kg
BS10Q
0.7 kg
BS12Q
0.8 kg
BS16Q
1.1 kg
Metric piping.
When using metric piping, replace the weight factors
in the formula by the ones from the following table:
Inch piping
Metric piping
Piping
Weight factor
Piping
Weight factor
Ø6.4 mm
0.022
Ø6 mm
0.018
Ø9.5 mm
0.059
Ø10 mm
0.065
Ø12.7 mm
0.12
Ø12 mm
0.097
Ø15.9 mm
0.18
Ø15 mm
0.16
Ø16 mm
0.18
Ø19.1 mm
0.26
Ø18 mm
0.24
Ø22.2 mm
0.37
Ø22 mm
0.35
Connection ratio requirements.
When selecting indoor units, the
connection ratio must comply with the following requirements. For
more information, see the technical engineering data.
6.7.4
To charge refrigerant
Follow the steps as described below.
Pre-charging refrigerant
1
Calculate the additional amount of refrigerant to be added using
the formula mentioned in
"6.7.3 To determine the additional
refrigerant amount" on page 28
.
2
The first 10 kg of additional refrigerant can be pre-charged
without outdoor unit operation:
If
Then
The additional refrigerant amount
is smaller than 10 kg
Perform steps 3~4.
The additional refrigerant charge
is larger than 10 kg
Perform steps 3~6.
3
Pre-charging can be done without compressor operation, by
connecting the refrigerant bottle to the service port of the liquid
stop valve (open valve B). Make sure that all outdoor unit stop
valves, as well as valves A, C, and D are closed.
NOTICE
During pre-charging, the refrigerant is charged through the
liquid line only. Close valves C, D, and A and disconnect
the manifold from the gas line and the high pressure/low
pressure gas line.
p< p>
R410A
N2
C
(1)
D
b
c
e
a
g
h
f
d
A
B
a
Pressure reducing valve
b
Nitrogen
c
Weighing scales
d
Refrigerant R410A tank (siphon system)
e
Vacuum pump
f
Liquid line stop valve
g
Gas line stop valve
h
High pressure/low pressure gas line stop valve
A
Valve A
B
Valve B
C
Valve C
(1)
D
Valve D
(1)
Only for heat recovery mode.
NOTICE
Do not connect the vacuum pump to the suction gas stop
valve if the unit is intended to run in heat pump mode. This
will increase the risk of unit failure.
4
Do one of the following:
If
Then
4a
The calculated additional
refrigerant amount is reached
by above pre-charging
procedure
Close valve B and disconnect
the manifold from the liquid
line.
4b
The total amount of
refrigerant could not be
charged by pre-charging
Close valve B, disconnect the
manifold from the liquid line,
and perform steps 5~6.
