Checking Refrigerant Piping: Setup; To Perform A Leak Test - Daikin VRV IV Q+ Series Installer And User Reference Manual

18.3.3 Checking refrigerant piping: Setup

18.3.4 To perform a leak test

To check for leaks: Vacuum leak test
RXYQQ8~20U7Y1B
VRV IV Q+ series heat pump
4P546229-1A – 2020.10
NOTICE
Do NOT purge the air with refrigerants. Use a vacuum pump to evacuate the
installation.
f
a
d
b c e
a Pressure reducing valve
b Nitrogen
c Weighing scales
d Refrigerant R410A tank (siphon system)
e Vacuum pump
f Charge hose
g Refrigerant charge port
h Gas line stop valve
i Liquid line stop valve
j Outdoor unit
k To indoor unit
l Stop valve
m Field piping
n Gas flow
o Stop valve service port
A Valve A
B Valve B
C Valve C
Valve
Valve A
Valve B
Valve C
Liquid line stop valve
Gas line stop valve
NOTICE
The connections to the indoor units and all indoor units should also be leak and
vacuum tested. Keep any possible (field supplied) field piping valves open as well.
Refer to the indoor unit installation manual for more details. Leak test and vacuum
drying should be done before the power supply is set to the unit. If not, see also the
flow chart earlier described in this chapter (see
4
piping" [ 89]).
The leak test must satisfy the specifications of EN378‑2.
1 Evacuate the system from the liquid and gas piping to –⁠ 1 00.7 kPa (–⁠ 1 .007 bar)
(5 Torr absolute) for more than 2 hours.
2 Once reached, turn off the vacuum pump and check that the pressure does
not rise for at least 1 minute.
j j j
g
A
h
i
B
C
o
Close
Open
Open
Close
Close
18 Piping installation
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k
l
m
n
State of valve
"About checking the refrigerant
Installer and user reference guide
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