© Edwards Limited 2008. All rights reserved.
Page 11
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Maintenance
A462-26-880 Issue F
5
Maintenance
5.1
Introduction
The life of the mist filter depends on the process application. For most applications, you should change the mist filter
element every six months. For applications which contaminate the rotary pump oil, this period will be reduced and
must be determined from experience. If the filter element becomes blocked, the pressure relief valve will operate
and allow unfiltered exhaust gases to pass through the filter.
Change the odour element monthly or whenever the pump emits an oily odour.
5.2
Change the filter elements
1. Switch off the electrical supply to the pump.
2. Wipe clean the outside of the filter.
3. Refer to
Figure 1
. Remove the drain plug (4) to drain the oil from the filter. When the filter is fully drained,
replace the drain plug.
4. If you have connected an exhaust pipeline to the filter outlet (1), disconnect it.
5. Undo and remove the four screws (12) which secure the upper body (10) to the lower body (7), then remove the
upper body.
6. Lift out the filter elements (8, 11) to be changed. Dispose of the used elements safely.
7. Wipe clean the inside of the upper body (10) and lower body (7) and the mating surfaces. Do not remove the
D-seal (9).
8. Ensure that the mist filter element O-ring (5) is in place in the lower body (7), then fit the new filter elements;
ensure that the foam sealing rings on the top and bottom of the elements are correctly seated.
9. Refit the upper body (10) to the lower body (7) and secure with the screws (12) removed in
Step 5
.
10. If fitted, reconnect your exhaust system pipeline to the filter outlet (1).
WARNING
Take all necessary precautions if toxic or dangerous substances have been pumped. Wear
protective clothing when you handle contaminated filters and filter elements.
WARNING
Ensure that the mist filter element O-ring is in place when you fit new filter elements. If you do
not, the pump exhaust gases will not be treated and oil mist will pass out of the mist filter into the
local environment and could cause injury to people.