[owenfi]

I put a Fantech SE704N in my WFH shed, which is 10x20 feet with 6-7 foot ceilings: Newer ERV: https://www.supplyhouse.com/Fantech-FIT70E-SE-Series-Energy-... In stock HRV: https://www.supplyhouse.com/Fantech-SH704-SH-Series-Heat-Rec... You can buy the core and swap HRV->ERV (not sure if FIT70E uses the same core).

I put it behind a Lutron Caseta Fan Speed controller, it struggles a bit to communicate due to range, but at the low settings I can barely hear it and it keeps CO2 PPM to ~1k if it's just me in here (usually), I turn it up to 3 if I want a gentle wind noise and rarely go to 4 (but would if I wanted to freshen it up). I used the Fantech 4" ducts and it was pretty easy to self-install.

[owenfi]

Oh, and to add, pre-installation the CO2 would hover around 2500ppm if the door and window were closed which was definitely noticeable.