Digital Manometer And Where To Put Hole For Probe

[velvetfoot]

I want to set up my baro damper. I just ordered a cheap digital manometer from eBay as well as a 4" right angle magnetic probe and am trying to figure out where to drill the hole for the probe. There is a short single wall transition piece (5" to 6") right after boiler exit before it changes to double wall DVL. After the transisiion, there's a 45 deg elbow and then a T that the baro damper is connected to. If I don't drill the hole in the transition piece I have to drill it in the double wall T. I'm leaning toward the transition piece, but it doesn't matter if it's that close to the boiler, does it? The probe will be metal. Perhaps the hole could also be used at some point to measure boiler performance. What do you think?

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[velvetfoot]

I am such a dumb ass. I looked at the installation manual (duh). There is a plugged hole in the exhaust. No drilling required.

Manual:
Adjust barometric damper according to the manufacturer‘s instructions. To access the measurement opening,
remove the back lid and the plug at the flue gas collar. Measure the draft with an appropriate analyzer. Adjust for
the flue draft listed on the boiler/heater name plate. Replace the plug and close the lid after measuring the draft.

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