VACUUBRAND PC 620 NT plastic housing - Manual (Page 43)

page 43 of 113
Important notes regarding the use of gas bal-
last
Gas ballast is a continuous purge to keep the pump’s in-
terior as clean as possible and to reduce the possibility of
condensation inside the pump.
➨
Air and pumped media might react inside the pump or
at the outlet of the pump and form hazardous or explo-
sive mixtures, when you use air rather than inert gas
for the gas ballast. This constitutes a risk of significant
damage to equipment and/or facilities, a risk of per-
sonal injury or even loss of life.
+
Make sure that air/gas intake through the gas ballast
valve can never lead to hazardous, explosive or other-
wise dangerous mixtures. If in doubt, use inert gas.
To reduce condensation in the pump, do not pump vapor
before the pump has reached its operating temperature.
Open the gas ballast valve when pumping condensable
vapors. Turn gas ballast cap to open valve.
For condensable vapors (water vapor, sol-
vents, etc.):
- The gas ballast valve is open if the arrow on
the gas ballast cap is pointing towards the
labelling ”GB”.
- With gas ballast valve open, the ultimate
vacuum will be reduced.
- Use inert gas for gas ballast to avoid the formation of
explosive mixtures. A special adapter fitting is needed
to connect an inert gas supply line (see “Accessories”,
pg. 86). This adapter replaces the standard gas bal-
last cap and allows for an inert gas line to be connect-
ed via a KF DN 16 small flange at a maximum supply
pressure of 17.5 psi (1.2 bar) absolute.
- Close the gas ballast valve by turning the cap 180°.
NOTICE
gas ballast (3)
(open)