When I checked my shop vac 20 gallon many years ago it only pulled 3" of vacuum so some duct tape and a hole for the gauge would probably be enough.
I think there may be an issue with the testing as some vacuum cleaners have a bypass system when vacuum pressures spike like from a clog they revert to the bypass so they can still suck in air without burning up the motor.
But I feel for a short quick test you could get a reading.
OK so I inserted the hose for my vacuum gauge into the vacuum cleaner hose and duct tapped around it.
One of my sharp vacuums with a bag i changed about a week ago recorded 5" vacuum and the other one with a couple month old bag recorded 4.5" vacuum. And no bag it pulled 5"
And my bags do not allow dust to come through and there is a filter after the bag but it is basically a spunge with huge holes on one vacuum and hepa on another, my bags are part number PU2 micro filtration with 99.7 % effifiency from envirocare for those Sharp vacuum cleaners and fits some Miele Vacuums also.
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I think there may be an issue with the testing as some vacuum cleaners have a bypass system when vacuum pressures spike like from a clog they revert to the bypass so they can still suck in air without burning up the motor.
But I feel for a short quick test you could get a reading.
OK so I inserted the hose for my vacuum gauge into the vacuum cleaner hose and duct tapped around it.
One of my sharp vacuums with a bag i changed about a week ago recorded 5" vacuum and the other one with a couple month old bag recorded 4.5" vacuum. And no bag it pulled 5"
And my bags do not allow dust to come through and there is a filter after the bag but it is basically a spunge with huge holes on one vacuum and hepa on another, my bags are part number PU2 micro filtration with 99.7 % effifiency from envirocare for those Sharp vacuum cleaners and fits some Miele Vacuums also.
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