Edge

Hey, #HVAC fans out there. I had looked into HRV/ERV systems several years ago due to very high CO2 levels in this house with only 2 people indoors, but the price, size, and extra ducting seemed prohibitive.

Just took a look around and apparently there are now ductless ERVs which seem like a great idea - basically I really just need an automated window to bring in or vent fresh air during the day.

Has anyone used pairs of these devices? Would love to hear experiences if you have some. Thanks.

#AQI #IAQ #HRV #ERV #FreshAir #GreenHomes

Jun 9, 2025 at 2:14amWeb
Show threadCamJun 9, 2025
@czarbucks I have been similarly curious about ERVs. The Home Performance and Healthy Home Guide YT channels have some info. (Sorry don’t have opportunity to provide specific links right now)
Show threadEdgeJun 9, 2025

@thoughtsofawho

Thanks, will look into those. I'm more of a reader, and found the green building advisor which had a lot of pretty good info (until I hit the paywall.)

Show threadkjellJun 9, 2025
@czarbucks I’ve been looking into them intending to retrofit one this summer. The benefit of the central design is it replaces however many exhaust-only bathroom fan(s). Central units can also use a single bigger, higher grade filter on the supply duct instead of however many small diameter “ductless” ducts. And fewer penetrations in the building envelope
Show threadkjellJun 9, 2025

@czarbucks Ditto the YT channels Cam mentioned above

And for asking this on fedi, https://www.openerv.ca/ might be worth looking into

OpenERV

Fresh outdoor air all year round.

Show threadkjellJun 9, 2025
@czarbucks Lastly - for adding on to an existing house, if you start with a forced air system, the ERV can piggyback on the existing supply ducts to simplify things. Ideally it’s a totally separate duct system but that’s not required
Show threadKiwiana 🦣Jun 9, 2025
@czarbucks We put one of these in my office as it was difficultto get ducting through the steel structure of the house to that room. It works well to exchange fresh air and includes heat recovery (although it will chill the room a bit on a cold day, you would want another heat source).
https://www.mitsubishi-electric.co.nz/ventilation/i/685034/single-room-fresh-air-ventilation-with-lossnay-energy-recovery
VL-100EU5-E : Single Room Fresh Air Ventilation with Lossnay Energy Recovery // Mitsubishi Electric

VL-100EU5-E. The wall-mounted VL100 Lossnay Fresh Air Energy Recovery Single Room Ventilation unit provides energy efficient ventilation to ensure individual rooms have a constant supply of healthy, fresh air with the additional benefit of energy efficient heat recovery at the same time. And because the unit is ductless in design, it means the system is ideal for homes and buildings where there is no roof space to install a heat exchanger. // Mitsubishi Electric Ventilation

Show threadEdgeJun 9, 2025

@Kiwiana13C

Thank you so much, this is just the kind of thing I was hoping to find experience with. Very helpful. 👍

Appreciate your post very much!