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Piping installation
Installer reference guide
44
3(A)MXM+3(A)MXF+4MXM+5MXM
R32 Split series
4P600463-1D – 2021.03
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.
3
Discharge all nitrogen gas.
7.3.4 To perform vacuum drying
DANGER: RISK OF EXPLOSION
Do NOT start the unit if it is vacuumed.
Connect the vacuum pump and manifold as follows:
a
h
b
f
h
i
e
c
d
e
g
j
a
Pressure meter
b
Gauge manifold
c
Low-pressure valeve (Lo)
d
High-pressure valve (Hi)
e
Charging hoses
f
Vacuum pump
g
Service port
h
Valve lids
i
Gas stop valve
j
Liquid stop valve
1
Vacuum the system until the pressure on the manifold indicates −0.1 MPa
(−1 bar).
2
Leave as is for 4-5 minutes and check the pressure:
If the pressure…
Then…
Does not change
There is no moisture in the system.
This procedure is finished.
Increases
There is moisture in the system. Go
to the next step.
3
Vacuum the system for at least 2 hours to a manifold pressure of −0.1 MPa
(−1 bar).
4
After turning the pump OFF, check the pressure for at least 1 hour.
5
If you do NOT reach the target vacuum or CANNOT maintain the vacuum for
1 hour, do the following:
▪
Check for leaks again.
▪
Perform vacuum drying again.
NOTICE
Be sure to open the gas stop valve after piping installation and vacuuming. Running
the system with the valve closed, the compressor may break down.