14 Charging refrigerant
Installation and operation manual
29
RXYSA4~6A7V/Y1B
VRV 5-S system air conditioner
4P600329-1A – 2020.01
NOTICE
Be sure to turn on the power 6 hours before operation in
order to have power running to the crankcase heater and
to protect the compressor.
NOTICE
If operation is performed within 12 minutes after the indoor
and outdoor units are powered on, the compressor will not
operate before the communication is established in a
correct way between outdoor unit(s) and indoor units.
NOTICE
Before starting charging procedures, check if the
7‑segment display indication of the outdoor unit A1P PCB
is as normal (see
"17.1.4 To access mode 1 or 2"
36]).
If a malfunction code is present, see
problems based on error codes"
NOTICE
Make sure all connected indoor units are recognised
(setting [1‑10]).
NOTICE
Close the front panel before any refrigerant charge
operation is executed. Without the front panel attached the
unit cannot judge correctly whether it is operating properly
or not.
NOTICE
In case of maintenance and the system (outdoor unit+field
indoor units) does not contain any refrigerant any
more (e.g., after refrigerant reclaim operation), the unit has
to be charged with its original amount of refrigerant (refer
to the nameplate on the unit) and the determined additional
refrigerant amount.
NOTICE
▪ Ensure that contamination of different refrigerants does
not occur when using charging equipment.
▪ Charging hoses or lines shall be as short as possible to
minimise the amount of refrigerant contained in them.
▪ Cylinders shall be kept in an appropriate position
according to the instructions.
▪ Ensure that the refrigerating system is earthed prior to
charging the system with refrigerant. See
connect the electrical wiring to the outdoor unit"
31].
▪ Label the system when charging is complete.
▪ Extreme care shall be taken not to overfill the
refrigerating system.
NOTICE
Prior to charging the system, it shall be pressure tested
with the appropriate purging gas. The system shall be leak
tested
on
completion
of
charging
but
prior
to
commissioning. A follow up leak test shall be carried out
prior to leaving the site.
14.2
To determine the additional
refrigerant amount
WARNING
The maximum allowable total refrigerant amount is
determined based on the smallest room being served by
the system.
See
"2.1.2 System layout requirements"
9] to determine
the maximum allowable total refrigerant amount.
INFORMATION
For final charge adjustment in a test laboratory, contact
your dealer.
INFORMATION
Note down the amount of additional refrigerant that is
calculated here, for later use on the additional refrigerant
charge label. See
"14.5 To fix the fluorinated greenhouse
30].
Formula:
R=[(X
1
×
Ø9.5
)×0.053+(X
2
×
Ø6.4
)×0.020]
R
Additional refrigerant to be charged [in kg and rounded off
to 1 decimal place]
X
1...2
Total length [m] of liquid piping size at
Øa
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
0.020
Ø6 mm
0.016
Ø9.5 mm
0.053
Ø10 mm
0.058
14.3
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>
N2
C
b
c
e
a
g
f
d
A
B
R32
a
Pressure reducing valve
b
Nitrogen
c
Weighing scales
d
Refrigerant R32 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
2
Open valves C and B.
