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karebearbennettgmail-comAdministratorApril 10, 2022 at 9:41 am
Posted by: @MarkH-2
Many years ago when I was on our board we had a similar problem; not wood fires, but odours from the exhaust vents from the building’s kitchen and bathroom extractor fans and sewage vent odours, as well as fumes from the old MAUs, being sucked into the air intakes of the MAUs.
Are you talking about exhaust from the MAU burner being sucked into the MAU intake?
The solutions were (1) more powerful MAUs; although the old ones met the 1979 building code, in 2005 they were no longer acceptable.
So more powerful MAUs were needed simply to meet 2005 code requirements, not as a solution to the odour problem?
In addition, (2) the air intakes for the MAUs were raised about 3.0 m /10 ft above the rest of the rooftop, providing access to cleaner air.
Interesting idea. But it might look kind of strange on our building which is relatively small.
Perhaps those solutions could work for you. An alternative might be to extend the chimneys to a greater height.
Yup, that would also work, but probably raising the MAU intake would be cheaper.
The chimney tops and the MAU intake are all on about the same level. One idea I have is to lower the MAU intake to the surface of the roof. I’m thinking it might be just low enough to allow any smoke to drift past a few feet higher.
I’m not an engineer so these are not technically appropriate suggestions; talk to a professional HVAC engineer.
I’m actually a mechanical engineer, but I have very little experience with HVAC. I would like to hire an HVAC engineer to look at it (if the board agrees), but I don’t know exactly where to find one. Do you know which company was used by your building?