Planning for an ERV
I recently bought an Airthings Wave, and set it up in our bedroom. I figured we’d have high CO2 at night, and sure enough, first two nights were 1100, and last night stayed at 1900 after friends came for dinner… Now I’m thinking I need to add ventilation. Our last energy audit 10 years ago showed 1610 cfm at ACH50 (not super tight, but…). Since then I replaced the oil furnace with a few mini splits, and did some more sealing…
The house is a 1700 sq ft 1960’s cape in Connecticut (Zone 5), with two (ish) bedrooms in a dormered upstairs, and the rest of life downstairs (kitchen, LR, office, etc…). We have a full basement (unfinished) and crawlspace above the 2nd floor where I could probably fit a small ERV, like a Panasonic Whisper Spot, or maybe run 4″ flex ducts…
If I follow the .35 ACH guidelines, then I’ll need roughly 80 cfm.
Suggestions on how I should set it up? Anyone else been here before?
Thanks!
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Replies
Andris,
Just out of curiosity, have you tried running a bath fan 24/7 and tracking your CO2 levels? I'm not wild about exhaust-only ventilation but...
Thanks for the reply, Steve. I'll do that, and report back (along with cracking open the bedroom window). Bath fan is downstairs (upstairs bath will get one when my honey-do list gets shorter!). Not crazy about adding an air leak to the house without trying to re-capture some of the heat being wasted, as well as very dry air in the winter.
I'll do that, and see how much the CO2 level changes.
If you don’t want to run ductwork you could look at the Lunos E2
https://foursevenfive.com/lunos-e/
They get installed in pairs and I believe up to 4 total can be controlled together.