Agilent Technologies G6600-90006 - Manual (Page 55)

Operation and Maintenance Manual 55
Note the position of the oil level in the window after operating the pump for
several hours. For the next several days of operation, recheck the oil level
daily. If the oil level is increasing, water is accumulating in the oil reservoir.
Confirm that the water vapor is properly being expelled from the oil mist
filter. If the oil level is dropping, excess air flow through the pump is forcing
oil out of the vacuum pump. Turn the restrictor plate so that the single
indentation on the restrictor plate is aligned with the indentation on the
side of the oil return assembly. After adjustment of the gas ballast, allow the
system to operate for an additional day and check the oil level again.
It is normal for the oil to appear foamy from air in the oil when viewing the oil
in the oil level window. The purpose of the ballast control is to sweep ambient
air into the pump oil. Ensure the oil level when the pump is operating is not
above the “Full” mark on the pump.