These Agilent Varian deluxe oil mist exhaust filters have KF25 (NW25) inlet and exhaust port connections and have a replaceable high efficiency oil separating cartridge. Its function is to purify the rotary vane vacuum pump's exhaust gas from aerosols of liquid vacuum pump oil (exhaust mist). These exhaust mist filters include an overpressure safety device which intervenes when the differential pressure reaches the 1 bar range. This prevents damage to the vacuum pump when the replaceable cartridge gets old and obstructed causing differential pressure across the filter media. It is advisable to replace the exhaust mist filter cartridge on a regular basis during your preventive maintenance schedule. The replaceable element cartridge is enclosed in the housing of the oil mist exhaust filter system. These oil mist filters can be upgraded with an additional oil return kit to allow the collected oil to be returned to the pump. The oil return kit is also sold on this web site. This pricing is for the Varian deluxe exhaust mist filter system only.

Manual Oil Drainage:
The oil on the case bottom must be periodically removed before it reaches the external surface of the cartridge to prevent loss in the filters mist removal efficiency. The window on the side of the case housing allows for checking the oil level. To drain the oil it is necessary to unscrew the plug on the underside of the filter case.

Maintenance & Filter Changing:
The cartridge has a limited life time that depends on the vacuum application. The cartridge clogging activates the by-pass device so that the gases from the pump are directly sent to the external ambient to avoid dangerous pump overpressures. In this case the oil mist is diffused into the atmosphere indicating that the cartridge is obstructed. This Varian exhaust mist filter can also be used with a oil return kit, Varian PN 9499376. The complete instruction manual in PDF format is available for download below