Being the curious person that I am, I couldn't stand it and had to try this lol.. I dilled a 1/4 inch hole two feet past the baro. First I looked at the mano and saw it was precisely at a .03" WC and the baro door was open at about a 60 degree angle letting air in. Then, I moved the mano probe to the location past the baro to discover it was in fact exactly the same.. I also stuck the mano probe into where combustion air flows in under the grates, and yet again I see a .03" WC on the mano....titleist1 wrote:hmmmm.... I was thinking it would be higher after the baro since the baro being open adds more air to the exhaust than is present at the manometer tube before the baro. But maybe that is a volume versus pressure difference. Although if the pressure after the baro wasn't higher, then it wouldn't open. hmmmmmm......looks like I'm gonna have to try it sometime.....but I am not betting any paychecks!!
I do know that if I close the baro the manometer reading (before the baro) goes up versus when it is open!
So now we know the rest of the story lol