Need help with manometer

[The Silver Bullet]

I have a dwyer 246 incline and home made vertical. I have the vertical one leg in the upper plenum and the other open to air, I t'd off the upper plenum to one leg of the incline and the other leg to the lower plenum...The problem I am haveing is more than likely operator but the incline appears to be mirroring the vertical??
How do I set the bench to 28" and get a reading on the incline?
I am sure that I am having a brain fart about this, but it has gotten on my last nerve.
The bench is a orfice with 6 115923 with three interchangeable plates, a 112cfm, 225cfm, and 450cfm.
Thanks for your help.

[larrycavan]

That setup should work the way you have it. Use the spreadsheet to verify what you think is happening is in fact happening. Dial up 10" of test pressure and cross check it against the inclined reading.