Nice!
Couple of comments:
- I think you have the right sensor. Yes they’re a little bulky.
- Be thoughtful about the inlet and outlet of the pms sensor. I think they’re designed to have a certain flow rate of air through them (they have an internal fan), so I would avoid interference with that due to the extractor fan air flow…
- Might not be so important for you as I guess the sensor isn’t on that large a % of the time, but consider life extension strategies.
- You could consider having this as just a stand alone sensor that is always on in the room. Throw some other sensors on there too…