Problems - FAQs Not Covered

FAQ

Dear Sir,
There is a HYvac 7 vacuum pump in our lab.

Both the gas ballast valve and the intake valve are closed, and the
original oil level is at the middle of the oil sight glass.

When it is turned on, the oil level goes up and reach the top of the
oil sight glass. When I just open the intake valve a little, the oil is
flashed out from the exhaust port and there is also oil leakage at the
gas ballast grommet.

Cloude you give me some ideas of the cause of this phemonenon? Is it
normal to see the oil level going up when the pump is running?

By opening valve you have a lot higher gas flow through the vacuum pump. When this happens oil molecules are carried with the gas flow.
This manifests itself with the appearance of oil mist or actual oil
droplets coming out the exhaust port of the pump.
The gas ballast grommet may be old and cracked and in need of replacement. Use of an upgraded HyVac "oil mist eliminator or true exhaust filter" on exhaust side of pump will help. Installing a section of pipe to boost exhaust opening of pump higher using 1/2 NPT plumbing pipe for HyVac 7, combinations or inclusion of all above suggested.