To Determine The Additional Refrigerant Amount; To Charge Refrigerant - Daikin VRV IV-S Installer And User Manual

6 Installation
6.7.3 To determine the additional refrigerant
amount
INFORMATION
For final charge adjustment in a test laboratory, contact
your dealer.
Additional refrigerant to be charged=R (kg). R should be rounded off
in units of 0.1 kg.
R=[(X ×Ø15.9)×0.18+(X ×Ø12.7)×0.12+(X
1 2
×0.022]
X =Total length (m) of liquid piping size at Øa
1...4
INFORMATION
Piping length is considered the distance from the outdoor
unit to the farthest indoor unit.
When using metric piping, please take into account following table
concerning the weight factor to be allocated. It should be substituted
in the formula for R.
Inch piping
Size (Ø) (mm) Weight factor
6.4 0.022
9.5 0.059
12.7 0.12
15.9 0.18
When selecting indoor unit, following table with connection ratio
limitation has to be respected. More detailed information can be
found in technical engineering data.
Used indoor Total capacity
units
(a)
CR
VRV DX 50~130%
RA DX 80~130%
(a) CR=Connection ratio.
6.7.4

To charge refrigerant

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 manual charging. It
can be skipped, but charging will take longer then.
Pre-charging refrigerant
Pre-charging can be done without compressor operation, by
connecting the refrigerant bottle to the service port of the liquid stop
valve.
1 Connect as shown. Make sure that all outdoor unit stop valves,
as well as valve A are closed.
p < p >
A B
g
f
a
d C
N2
b c e
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
A Valve A
B Valve B
C Valve C
Installer and user reference guide
24
×Ø9.5)×0.059+(X ×Ø6.4)
3 4
Metric piping
Size (Ø) (mm) Weight factor
6 0.018
10 0.065
12 0.097
15 0.16
Allowable capacity connection
ratio
VRV DX RA DX
50~130% —
— 80~130%
2 Open valves C and B.
3 Pre‑charge refrigerant until the determined additional refrigerant
amount is reached or pre‑charging is not possible anymore, and
then close valves C and B.
4 Do one of the following:
If
The determined additional
refrigerant amount is reached
Too much refrigerant is
charged
The determined additional
refrigerant amount is not
reached yet
Charging refrigerant (in manual additional refrigerant charge
mode)
The remaining additional refrigerant charge can be charged by
operating the outdoor unit by means of the manual additional
refrigerant charge mode.
5 Connect as shown. Make sure valve A is closed.
p < p >
A
d
b
R410A
a c
a Weighing scales
b Refrigerant R410A tank (siphon system)
c Vacuum pump
d Refrigerant charge port
A Valve A
NOTICE
The refrigerant charging port is connected to the piping
inside the unit. The unit's internal piping is already factory
charged with refrigerant, so be careful when connecting
the charge hose.
6 Open all outdoor unit stop valves. At this point, valve A must
remain closed!
7 Take all the precautions mentioned in
page 29 and "8 Commissioning" on page 39
8 Turn on the power of the indoor units and outdoor unit.
9 Activate setting [2‑20] to start the manual additional refrigerant
charge mode. For details, see
page 33.
Result: The unit will start operation.
Then
Disconnect the manifold from
the liquid line.
You do not have to perform the
"Charging refrigerant (in
manual additional refrigerant
charge mode)" instructions.
Recover refrigerant.
Disconnect the manifold from
the liquid line.
You do not have to perform the
"Charging refrigerant (in
manual additional refrigerant
charge mode)" instructions.
Disconnect the manifold from
the liquid line.
Continue with the "Charging
refrigerant (in manual
additional refrigerant charge
mode)" instructions.
8 HP 10+12 HP
d
d
"7 Configuration" on
into account.
"7.2.8 Mode 2: Field settings" on
RXYSQ8~12TMY1B
VRV IV-S system air conditioner
4P404225-1B – 2016.03