Recommend 1402 Exhaust Filter?

[johnp]

Hi,

One of our physics labs has a 1402 in good working order; however, I have been concerned about the small amount of oil vapor coming from it, as it vents into the lab room space and not into a snorkel or other safe route. The pump has an exhaust filter but I'm wondering if it needs a new one or a better one that captures more vapor.

When I look for 1402 exhaust filters a search comes up with things like this:

http://www.mscdirect.com/product/detail ... 0=01815992

[Nick Peskosky]

John,

The oil vapor coming from the exhaust is of minimal safety concern and poses more of a nuisance (it will condense on surfaces) to keeping lab surfaces clean. If you're running the Welch without a closed chamber it will continue to produce vapor due to the increased gas load (= increased thermal loading) that is being placed on the pump's mechanical stages, this also applies to pumping with the gas ballast open. Confirm whether or not the blanked off pump is still producing an unreasonable amount of exhaust mist and if so then you may want to consider the following:

1. Ensure the gas ballast is completely closed
2. Check that your pump is filled with the proper vapor pressure vacuum oil
3. Replace the filter membrane
4. Forgo the expensive filter in your attached link and just place an adapter on the exhaust to convert to a standard KF fitting (http://welchvacuum.com/products/inlet-e ... ting-1393g) and use any run-of-the-mill exhaust filter found on eBay which is rated for your pump's displacement

[Werner Engel]

I used a 10 Liter bottle massivly stuffed with cotton wool - does the same job, much cheaper!