To Perform Vacuum Drying - Daikin 3MXM40N2V1B9 Installer's Reference Manual

7 | Piping installation

7.3.4 To perform vacuum drying

Installer reference guide
44
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.
DANGER: RISK OF EXPLOSION
Do NOT start the unit if it is vacuumed.
Connect the vacuum pump and manifold as follows:
a
c d
b
e
e
i
h
f
g
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...
Does not change
Increases
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.
j
h
There is no moisture in the system.
This procedure is finished.
There is moisture in the system. Go
to the next step.
Then...
2MXM68+3(A)MXM+3(A)MXF+4MXM+5MXM
R32 Split series
4P600463-1D – 2021.03