Rotary Pump Oil; Oil Quality; Oil Color; Gas Ballast Control - Waters GCT Premier Operator's Manual

Should a fault occur soon after a particular part of the system has been
repaired or otherwise disturbed, first ensure that the part is correctly refitted
and /or adjusted. Then determine whether adjacent components have not been
inadvertently disturbed.

Rotary pump oil

Oil quality

It is important that the recommended oil type is used for the associated rotary
pump and vacuum conditions. For example, if the vapor pressure of the oil is
higher than the ultimate vacuum of the pump, the instrument will not achieve
its ultimate vacuum level. The condition of the oil is also critical to the rotary
pump performance. If the oil is contaminated, the pump may operate at a
reduced speed. With single phase pumps, if the pump continues to operate at
reduced speed, the thermal overload opens and stops the pump. This
spontaneous stopping of the pump must be avoided because it causes the
instrument to perform an emergency vent.
Checking the rotary pump oil on page
See also:

Oil color

The color of the oil indicates its current quality. It can be checked through the
oil level sight glass. The oil in the pump should be clear. If the oil is cloudy or
discolored, it is contaminated with process vapors and must be replaced.
See also: Changing the rotary pump oil on page

Gas ballast control

The rotary pump gas ballast control changes the flow of gas ballast into the
low-vacuum stage of the pump, releasing the trapped process vapors to
exhaust. The color of the oil should return to clear.
Gas-ballasting the rotary pump on page
See also:
10-4 Routine Maintenance
10-6.
10-7.
10-5.