Fusor Forums

So I got this gauge (2000+ new) for like $200 on eBay and I've been having some issues with it. I attached it directly to the output of my diff pump and pulled a vacuum through it with my backing pump, and got like 15 torr. The pump was very loud, so I assumed it was my shoddy job of re-using a conflat gasket. I replaced the gasket, and when I pulled vacuum again the pump was whisper-quiet after I closed the ballast. However, the gauge still read 15 torr. This may be an internal issue with my gauge, but I was wondering if this auditory indicator is a valid way of determining vacuum quality.
Thanks,
-Duncan

Rotary vane pumps definitely get quiet when the pressure and gas load are small, but it's not terribly sensitive.

Could be a problem with the pirani element, they are known to go bad on these gauges.

Send it back and get your money back, I usually dont spend more than $100 on these units.