Make-up air strategy
We are in Minnesota (Zone 6a). 2200 sq/ft single level, slab on grade. We have a heat pump (no central ducted system) and an HRV.
Both my HVAC contractor and I missed/forgot to plan a strategy for make up air. Even though I submitted table 501.3.1 for my building permit and determined I need a 4″ round passive duct for 39 CFM of make up air using a 300 cfm range hood fan, we just forgot about that requirement.
I have read
https://www.greenbuildingadvisor.com/article/passive-air-inlets-usually-dont-work but I have yet to perform a blower door test. I hope I have a very tight house. Perhaps I should have the test done before making a decision?
I would like to put a simple duct with a damper through the wall behind the slide in style 30″ gas range, am concerned that using a spring loaded damper or a cape hood damper will not be reliable long term. Is this concern founded?
A motorized damper seems more reliable, but I would not have the room behind the range, so I would have to install it in the attic, interlock with the hood, and have the make up air come across the kitchen ceiling. Plus I’m not finding a 4″ motorized damper….only 6″+. Any suggestions on which route I should go? I could just do a recirculating fan and eliminate the issue all together, but I do prefer to have some venting.
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