How do you guys set up ur manometer

I've seen the brake line idea but I'm looking for more specifics do I need to put a 90ﾟ bend on the end the brake line just leave it ran straight into the pipe what's the best method

If you experiment, like I did, you'll find the readings differ from having the tip of the brake tubing near the pipe wall - where wall resistance to flow slows it- to having it in the center where the exhaust flow is faster. Velocity of the exhaust leaving the stove is part of what causes the stove's draft. It's a result of the pressure differences inside and outside the stove and chimney system. Mano's are also used to measure gas flow speed, not just pressure drop and when doing that the probes are placed near the center of flow for accuracy.

The exhaust gas has mass and velocity, just like if you held the tube out the window of a moving car. Just less mass than air at the same altitude. That's why the heavier room air is pushing into the stove creating draft.

Bending the tip to face into the stream will lower the readings as the exhaust hits and tries to push into the tube.

Having the tip opening 90 degrees to the exhaust flow will cause a natural venturi effect - a pressure drop- and give higher than normal readings of the exhaust flow's pressure relative to outside the pipe. That's how the discharge jet of a carburetor moves heavier fuel uphill from the fuel bowl to mix with air going into the engine.

Bending the tip to face with the exhaust flow will give the readings closer to actual.

And that bit of "gassing on" is the short version of what happens.

Paul

Good info there that's exactly what I was looking for so bent with the end facing the baro with the direction of flow of exhaust in the center of the pipe is the way to go then thankyou very much