![background image](http://html.mh-extra.com/html/daikin/rxm20a5v1b/rxm20a5v1b_installers-reference-manual_4189284041.webp)
7
|
Piping installation
Installer reference guide
41
RXM-A, ARXM-A
R32 split series
4P718129-3A – 2023.07
7.3.3 To check for leaks
NOTICE
Do NOT exceed the unit's maximum working pressure (see "PS High" on the unit
name plate).
1
Charge the system with nitrogen gas up to a gauge pressure of at least
200 kPa (2 bar). It is recommended to pressurize to 3000 kPa (30 bar) in order
to detect small leaks.
2
Check for leaks by applying the bubble test solution to all connections.
NOTICE
ALWAYS use a recommended bubble test solution from your wholesaler.
NEVER use soap water:
▪
Soap water may cause cracking of components, such as flare nuts or stop valve
caps.
▪
Soap water may contain salt, which absorbs moisture that will freeze when the
piping gets cold.
▪
Soap water contains ammonia which may lead to corrosion of flared joints
(between the brass flare nut and the copper flare).
3
Discharge all nitrogen gas.
7.3.4 To perform vacuum drying
DANGER: RISK OF EXPLOSION
Do NOT open the stop valves before the vacuum drying is finished.
Connect the vacuum pump and manifold as follows:
i
h
j
a
b
c
h
k
d
f
f
e
g
a
Low pressure gauge
b
Gauge manifold
c
High pressure gauge
d
Low-pressure valve (Lo)
e
High-pressure valve (Hi)
f
Charging hoses
g
Vacuum pump
h
Valve caps
i
Service port
j
Gas stop valve
k
Liquid stop valve
1
Vacuum the system until the pressure on the manifold indicates −0.1 MPa
(−1 bar).