Other accessories can be installed without any problem. They are supplied with recirculating oil lubrication as standard (with integrated oil cooler) and sealing cap, which reduces the noise emitted to a minimum. A float valve regulates the oil re-circulation, which means that the vacuum pumps can also be used in coarse vacuum applications. An optional (not standard) water cooling device for the oil considerably extends the service life of the oil, even in very demanding working environments.

Optional gas ballast valves prevent condensate vapours from contaminating the pump oil. The resulting emulsion of water and oil would impair pump performance or cause pump failure. The valve allows a certain amount of dosed fresh air (the gas ballast) to enter the pump’s compression chamber. The mixture of saturated suction air and unsaturated fresh air inhibits condensation.