Use ERV ducting for possible future forced air furnace?
Climate zone 6B.
I have gotten great advice here pertaining to heating my new construction high performance house. I am confident that mini-splits will provide enough heat for us when used with the masonry stove. I think I will plan on additional electric back up for an office and a bathroom for comfort. Many, respected, local HVAC people think I’m wrong.
My current dilemma is that I might be building a house that, when the time comes, would be difficult to sell. We have a climate with more heating degree days than almost anywhere else in the world. This makes building a high-performance house a logical choice. It also makes decisions of all systems more demanding.
This brings me to the need for a heating back up plan. I do not have a problem with starting a fire and maybe using some electric room heat in the coldest weather, but most home buyers would expect to set the thermostat and forget about it.
I have two Panasonic Intelli-Balance 100, Cold Climate ERV 50-100 CFM – FV-10VEC1. The house is slightly larger than one unit can handle, and I thought I could just run one of them most of the time. Everything we would need is on one level with guest bedrooms upstairs and an unfinished basement. (basement and 2nd floor on one ERV and main level on the other). Fully dedicated ducted installation.
The current backup plan would be to oversize the ERV ductwork, then if the mini-splits prove to be inadequate or the next home owner wanted a furnace for ease of operation, a 30,000 BTU forced air furnace could use the existing ductwork.
On the surface this seems like a logical option but the more I think about, the more I question if I’m not creating more problems than I’m solving. 1. Would oversized ductwork be difficult to control flow to each floor and room? 2. Would the stack effect create problems with the ERV supplying the basement and second floor? (I thought the second-floor air could come out at the floor and the basement at the ceiling, but it would still be a difference in height of around 12 feet. 3.Can two ERVs provide fresh air to one furnace? They would cycle independently and if run constantly would need to run the furnace fan all the time, so the fresh air would flow the correct way. Right?
Thanks for the continued support. These are important decisions.
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