To Charge Refrigerant - Daikin VRV IV W+ Series Installer And User Reference Manual

18 | Piping installation

18.5.4 To charge refrigerant

Installer and user reference guide
98
Follow the steps as described below.
Pre-charging refrigerant
1 Calculate the additional amount of refrigerant to be added using the formula
mentioned in "18.5.3 To determine the additional refrigerant
2 The first 10 kg of additional refrigerant can be pre-charged without outdoor
unit operation:
If
The additional refrigerant amount is
smaller than 10 kg
The additional refrigerant charge is
larger than 10 kg
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 >
A B
a
d
N2 R410A
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
h High pressure/low pressure gas line stop valve
A Valve A
B Valve B
(1)
C Valve C
D Valve D
(1) Only for heat recovery system.
NOTICE
Do not connect the vacuum pump to the suction gas stop valve if the unit is intended
to run as a heat pump system. This will increase the risk of unit failure.
4 Do one of the following:
4a The calculated additional
refrigerant amount is reached by
above pre-charging procedure
Perform steps 3~4.
Perform steps 3~6.
C D
(1)
h
g
f
If
Close valve B and disconnect the
manifold from the liquid line.
4
amount" [ 96].
Then
Then
RWEYQ8~14T9Y1B
VRV IV water-cooled system air conditioner
4P452191-1B – 2020.10