About Charging Refrigerant; To Determine The Additional Refrigerant Amount - Daikin VRV 5 RXYA8A7Y1B Installation And Operation Manual

16.2

About charging refrigerant

Once vacuum drying and leak test are finished, additional refrigerant
charging can start.
To speed up the refrigerant charging process, it is in case of larger
systems recommended to first pre-charge a portion of refrigerant
through the liquid line before proceeding with the actual charging.
This step is included in below procedure (see
refrigerant" [ 4 38]). It can be skipped, but charging will take longer
then.
A flow chart is available which gives an overview of the possibilities
and actions to be taken (see
chart" [ 4 38]).
16.3 To determine the additional
refrigerant amount
WARNING
The maximum indoor capacity index which can be
connected to a SV unit port is determined based on the
smallest room served by that port.
In case the system serves the lowest underground floor of
a building, there is an extra limit to the maximum allowable
total refrigerant amount. This maximum refrigerant amount
is determined based on the area of the smallest room on
the lowest underground floor.
See "13 Special requirements for R32
determine the maximum allowable total refrigerant amount.
INFORMATION
For final charge adjustment in the test laboratory, please
contact your local dealer.
INFORMATION
Note down the amount of additional refrigerant that is
calculated here, for later use on the additional refrigerant
charge label. See "16.8 To fix the fluorinated greenhouse
label" [ 4 40].
gases
NOTICE
The refrigerant charge of the system must be less than
79.8 kg. This means that in case the calculated total
refrigerant charge is equal to or more than 79.8 kg you
must divide your multiple outdoor system into smaller
independent systems, each containing less than 79.8 kg
refrigerant charge. For factory charge, refer to the unit
name plate.
NOTICE
The total refrigerant charge amount in the system MUST
always be lower than 79.8 kg.
Formula:
R = [(X × Ø19.1) × 0.23 + (X × Ø15.9) × 0.16 + (X
1 2
+ (X × Ø9.5) × 0.053 + (X × Ø6.4) × 0.020] + (A + B + C)
4 5
R Additional refrigerant to be charged [kg] (rounded off to
one decimal place)
X Total length [m] of liquid piping size at Øa
1...5
A~C Parameters A~C (see below)
INFORMATION
▪ In case of a multi-outdoor-unit system, add the sum of
the individual outdoor unit charge factors.
▪ When using more than one SV unit, add the sum of the
individual SV unit charge factors.
RYMA5+RXYA8~20A7Y1B
VRV 5 heat pump
4P739915-1 – 2023.12
"16.5 To charge
"16.4 To charge refrigerant: Flow
units" [ 4 19] to
× Ø12.7) × 0.10
3
16 Charging refrigerant
▪ Parameter A: If the total indoor unit capacity connection ratio
(CR)>100%, charge an additional 0.5 kg of refrigerant per outdoor
unit.
▪ Parameter B: Outdoor unit charge factors
Model
RYMA5
RXYA8~12
RXYA14
RXYA16
RXYA18
RXYA20
▪ Parameter C: Individual SV unit charge factors
Model
SV1A
SV4A
SV6A
SV8A
Metric piping. When using metric piping, replace the weight factors
in the formula by the ones from the following table:
Inch piping
Piping Weight factor
Ø6.4 mm 0.020
Ø9.5 mm 0.053
Ø12.7 mm 0.10
Ø15.9 mm 0.16
Ø19.1 mm 0.23
Parameter B
0 kg
1.2 kg
1.3 kg
4.3 kg
Parameter C
0.4 kg
0.5 kg
0.7 kg
0.9 kg
Metric piping
Piping Weight factor
Ø6 mm 0.016
Ø10 mm 0.058
Ø12 mm 0.088
Ø15 mm 0.14
Ø16 mm 0.16
Ø19 mm 0.22
Installation and operation manual
37