Daikin VRV 5 - Checking Refrigerant Piping: Setup; To Perform a Leak Test

18 | Piping installation
Installer and user reference guide
104
RXYSA8~12AMY1B
VRV 5-S system air conditioner
4P752782-1A – 2024.02
NOTICE
Make sure the pump oil does not flow oppositely into the system while the pump is
not working.
NOTICE
Do NOT purge the air with refrigerants. Use a vacuum pump to evacuate the
installation.
18.3.3 Checking refrigerant piping: Setup
p
<
p
>
C
b c e
a
g
f
d
A B
R32 N
2
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
Valve Status
Valve A Open
Valve B Open
Valve C Open
Liquid line stop valve Close
Gas line stop valve Close
NOTICE
Indoor units should also be leak and vacuum tested. Keep any possible (field
supplied) field piping valves open as well.
18.3.4 To perform a leak test
The leak test must satisfy the specifications of EN378‑2.
Vacuum leak test
1 Evacuate the system from the liquid and gas piping to a gauge pressure of
–⁠100.7kPa (–⁠1.007bar) 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.
3 Should the pressure rise, the system may either contain moisture (see vacuum
drying below) or have leaks.