ERV/HRV, central system vs select multiple units
I did my best to “build it tight”, sealed/caulked/taped framing, XPS outsulation caulked and taped at seams, multiple WRBs (below and above the outsulation, etc…
Now the “ventilate it right” issue is my next challenge. Looking for good advice. opinions, input.
I am in Zone 5, single family home, forced hot air/HVAC and looking at ventilation options. Considering a typical central ERV/HRV and running ventilation-only ducting/tubes. HVAC guy seemed to have lots of issues with LVLs and register placement. As I walk around the structure I appreciate the challenge. Was considering the feasibility of say two smaller ERV/HRVs on opposite ends of the home to limit ducting rather than a central basement unit. All bathrooms already have a vent fan. House has a wood burning stove to be used as primary source of heat. Fresh air entry and possibility of creating negative pressure with kitchen hood and bathroom vents on while wood burning stove is roaring away concerns me.
What do you think of 2 smaller “local” systems. Positioned on the first floor, say one drawing air out of kitchen the other from wood burning stove area and feeding back into hallways and/or bedrooms. Would save on cost of and labor of running tubes, albeit there is the cost of another unit, but smaller. Run one continuously, drawing from kitchen, while the other kicks in on only demand – wired to bathroom and kitchen exhaust vents, to augment entry to avoid negative pressure.
Thanks
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I'm a "fan", pun intended, of one or two ERVs in separate locations running 24/7, depending of the size of your house and ERVs, and I happen to like Panasonic Whisper Comfort and FanTech brands. I don't get why anyone with forced air heating and cooling would install a wood appliance in a tight building envelope house, even with a tight door seal... I do realize wood stoves are Northerner's thing!
Sal, how big is your house? Did you do a blower door test? There are several ductless ventilation systems that might work for you.
Done right, the ventilation system can/should replace your bath fans.
I think fresh air intake for a wood stove is a must!
Since HRV/ERV's are balanced ventilation, what happens when a range vent or multiple bathroom vents turn on? Like Sal said a negative pressure should be created, or will additional CFM's come in through the fresh air side of the "balanced ventilation" HRV/ERV.