Does anybody know how I should physically mount BMP280 to measure air pressure in heating duct?

Unsure if this is the best place to post this, but in the wider sense this is about “hardware”; I will move it if there’s a better place :worried: .
I’m trying to measure the air pressure in my heating ducts with two BMP280 sensors: one before and one after the air filter. The first obvious application is to know when my filter needs changing but there may be others.

I have the electronics and yaml code sorted and working on a breadboard; I’m impressed how close to each other the two sensors are reading; both pressure and temperature!
Anyway, I now need to figure out how to physically connect the sensors to the air duct.
It seems I should, somehow, glue/epoxy/attach some flexible plastic tube (wide enough to surround the chip) to the PCB, and stick the other end inside the duct through a hole.
Then does it matter if my tubes stick inside the vent an arbitrary length and if they may bend, or should I try to make them flush with the duct wall?
Is there a better solution? What if I stick the whole breakout board inside and just get the wires out?
In this care I worry that the orientation relative to the airflow may matter and even if I orient them the same (let’s say I stick the PCB back to the wall), how are the readings affected by the airflow?
I realize I don’t need a perfect “solution” for my purpose, but it would be nice to know.
Thank you all in advance.

There’s a bit of discussion here: Furnace filter differential pressure sensing?

Pointing downstream seems to be the go.

I would avoid putting the sensor directly in the duct if there is any chance of condensation or (upstream of the filter) anything blocking the small sensor hole.

Thank you @tom_l ; I don’t know why I didn’t find it myself… maybe because my search included too many terms :frowning: .

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