# Vacuum pump won't hold a vacuum



## Wayne1 (Jul 3, 2009)

Hello to anyone who uses a vacuum pump for depumping - I just recently purchased this InvaCare pump off of Ebay and tried using it today to degas. It draws a vacuum easily while running but as soon as I turn it off, I can hear air whooshing and the vacuum is gone. The air seems to be rushing in somewhere internally. I think it is supposed to hold a vacuum - isn't that correct? Has anyone else had this problem?
Thanks for any ideas,
Wayne


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## grapeman (Jul 3, 2009)

These vacuum pumps do not hold a vacuum. They pump while the motor is on and then lose vacuum as air is drawn in from wherever it can get it. Attach it to the carboy, run the pump until the bubbles stop and shut it off. It should get all the gas out in about 5 minutes. 




You can also use this pump to transfer from a source to a GLASS carboy. It doesn't work with the Better Bottles.


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## Wade E (Jul 3, 2009)

Actually if you build up pressure and then shut it off and fully close off the knob it will hold the pressure or at least it does on mine as thats what I do.


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## gaudet (Jul 4, 2009)

If you installed a petcock between the canister and the tubing (bypassing the gauge) you could probably hold the vacuum. But you don't need to do that. As Rich said you are pretty much finished after 5 minutes or when the bubbles stop coming.


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## Wayne1 (Jul 4, 2009)

ok - I did not close off the knob so maybe that was why it was leaking - after the other comments, maybe I will just let it run several minutes as suggested
thanks for the responses,
Wayne


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