Yellow jacket guage leak?

I have a micron guage. It’s the yellow jacket unit. Should it hold vacuum when vac is off? Because if I turn off my vac the unit starts to rise in microns. (Connected straight to pump)

Connected straight to pump as in no isolation or shut in valve? How can you be sure the leak is your guage and not atmosphere leaking back through the pump itself?


So I put a valve on the pump. It still leaks when I turn the pump off. I just got a new pump and the guy at the store put it on a micron guage directly to the kf25 (analog) and it got below 10 micron. On mine best is 37 micron

I have yellow jacket unit, have you done the sensor calibration and setup on your unit properly? they have it on