6 Installation
Installer and user reference guide
26
RWEYQ8~1 RWEYQ8~14T9Y1B
VRV IV water-cooled system air conditioner
4P452191-1 – 2017.04
a
c
d
b
a
Service port and service port cover
b
Stop valve
c
Field piping connection
d
Stop valve cover
2
Connect the vacuuming/recovery unit through a manifold to the
service port of all stop valves.
p< p>
R410A
N2
b
c
e
a
f
g
h
d
A
C
(1)
D
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.
3
Recover gas and oil from the pinched piping by using a
recovery unit.
CAUTION
Do not vent gases into the atmosphere.
4
When all gas and oil is recovered from the pinched piping,
disconnect the charge hose and close the service ports.
5
Cut off the upper part of the liquid, gas, and high pressure/low
pressure gas stop valve pipes along the black line. Use an
appropriate tool (e.g. a pipe cutter, a pair of nippers).
WARNING
Never remove the pinched piping by brazing.
Any gas or oil remaining inside the stop valve may blow off
the pinched piping.
6
Make sure that no particles remain in the pipe. Blow out any
particles with compressed air.
7
Wait until all oil is dripped out before continuing with the
connection of the field piping in case the recovery was not
complete.
6.5
Checking the refrigerant piping
6.5.1
About checking the refrigerant piping
Refrigerant piping works are
finished?
The indoor units and/or
outdoor unit were already
powered ON?
Use procedure:
"Method 2: After power ON".
Finish piping work.
Use procedure:
"Method 1: Before power ON
(regular method)".
Yes
No
No
Yes
It is very important that all refrigerant piping work is done before the
units (outdoor or indoor) are powered on.
When the units are powered on, the expansion valves will initialise.
This means that they will close. Leak test and vacuum drying of field
piping and indoor units is impossible when this happens.
Therefore, there will be explained 2 methods for initial installation,
leak test and vacuum drying.
Method 1: Before power ON
If the system has not yet been powered on, no special action is
required to perform the leak test and the vacuum drying.
Method 2: After power ON
If the system has already been powered on, activate setting [2‑21]
(refer to
"7.2.4 To access mode 1 or 2" on page 36
). This setting
will open field expansion valves to guarantee a R410A piping
pathway and make it possible to perform the leak test and the
vacuum drying.
NOTICE
Make sure that all indoor units connected to the outdoor
unit are powered on.
NOTICE
Wait until the outdoor unit has finished the initialisation to
apply setting [2‑21].
Leak test and vacuum drying
Checking the refrigerant piping involves:
▪ Checking for any leakages in the refrigerant piping.
