ERV placement – worth the candle?
The house has two systems, three zones. One zone covers the main floor and basement. The basement is finished with almost zero space left for mechanicals.
There is an unused vent to the exterior ( old dryer ) next to a stairwell. Underneath the stairwell is space for an ERV in a semi-finished closet.
I would like to hear people’s thoughts on three options:
1. Connect the ERV to the ductwork running across the middle of the basement ceiling in a soffit. Is there a way to do this without removing drywall in a continuous strip from the ERV to the ductwork?
2. No connection between the ERV and the HVAC system. Instead, ERV would draw air from the basement’s main room while returning it to the laundry room. On the main floor, the only place I can see for a vent to either draw or return is the stairwell. Two limitations: the HVAC return is also there and the stairwell is open to the upstairs, where other ERV has shares its return with the HVAC.
3. Lunos-style through-wall ERVs. Not sure about placement since one side of the house hosts two combustion appliances plus the radon system.
I guess there’s another option. The air upstairs does not seem fresh, but on the main floor the problem seems to be more of a lingering odor. Obviously, when we bought the house, we should have ozone-treated and repainted, but now the house is full of our stuff. Instead of an ERV, should I ozone-treat? Aside from removing leather couches, what else needs to be protected?
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Replies
Don't ozone treat..it's not safe for living spaces and will for sure introduce wierd odours and/or chemical changes in fabric etc. I'd only do this in an empty house.
It might make more sense to deliver fresh air to the main area, and exhaust from the laundry. Having a standalone system is fine although you'd ideally have supply on both the main floor and 2nd floor as well as a return in either space if there is not a clear path via open stairwells to your basement laundry return.
I have a 2 story house with basement and one HRV with a single return (basement stairwell) and one supply in the main floor living area. I run the ECM furnace fan at about 300 CFM at night to address the 2nd floor bedrooms. Monitoring CO2 on all three floors, that setup works fine.
See Corbett Lunsford on YouTube, Ozone generators are not a good idea. Good old-fashioned pleated media filters are the best bet.
Ok, I won’t ozone treat unless the house is emptied. I never considered adding ozone with people in the house. Next house, I will do it before we move in.
The stairwell to the basement is closed, so there is not a great route for air circulation. Plus, the odor problem is confined to the main floor.