I air sealed and insulated a previously-vented 250 sqft and 3ft tall crawlspace below a 700 sqft single-story living area with insulated walls and very few windows. It's heated and cooled by a Bryant 820TA 80% 45,000 BTU and 1.5 ton AC unit.
There is an 8"x16" supply trunk running through the crawlspace, and a single 12"x12" return in the ceiling. There are nine 6" round branches from the trunk, anywhere from 5' or so long to 20 feet long.
I would like to condition the crawlspace air by cutting in a 6" saddle or two on supply branches down there, and adding a passive return grill in the floor between the first floor and crawl.
I realistically am not going to fully study HVAC science to get this exactly right, but what are the risks as far as my system is concerned in proceeding with this? Is there any before and after testing I can do?
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There is an 8"x16" supply trunk running through the crawlspace, and a single 12"x12" return in the ceiling. There are nine 6" round branches from the trunk, anywhere from 5' or so long to 20 feet long.
I would like to condition the crawlspace air by cutting in a 6" saddle or two on supply branches down there, and adding a passive return grill in the floor between the first floor and crawl.
I realistically am not going to fully study HVAC science to get this exactly right, but what are the risks as far as my system is concerned in proceeding with this? Is there any before and after testing I can do?
