Hey HVAC Mags, Do I Need an HRV Air Exchanger

[jerlane]

We are doing a whole house remodel, basically new build at this point. One HVAC guy recommends an air exchanger, the other does not.

I like the second guy better, he is from Centerpoint and doesn't come across as a used car salesman. The other does.

The quote for one is $1750. Not a small ticket item. What's the reality? Do we really need one? We live in Minneapolis if that helps.

Thanks!

[ctsmith]

Probably not, but run a blower test so you know how well air sealed your house is. I doubt you'll be under 2.0 for ach50, and I wouldn't put in an HRV if you're above 2.0.

[BigDaddy]

Blower test is a great idea, but it's probaly something that has to be installed while the renovation is under way. If you're super insulating (ie- foam or multiple layers) you should consider it. $1750 isn't bad if it includes installation. I did one on my own for maybe $900, so you're paying $900 for a professional install. Not too bad if they know what they're doing. It's a lot of work.

You want to be breathing fresh air and this will insure that you do. I love mine for that reason alone. And in the same vein, fuck Trump.

[jerlane]

Blower test looks expensive. $500? Does that sound right. FYI, we have spray foam in the basement and blow-in in the rest of the house. I don't think that would qualify as "super insulated." Also, the roof has vents and the attic space has blow in insulation with a vapor barrier.

[BigDaddy]

How many square feet and how many rooms? If it's a small house, you could easily do the install while things are gutted and open. If it's a big house (2000 sq ft and above), then it may be more sophisticated requiring more duct work, etc. If you're kind of handy, you could still do it. Not really rocket science.... not even close. It would take you about a day.

[ctsmith]

From your description it sounds like you'll be getting plenty of outside air through infiltration. Insulation and air sealing are generally different things, with the exception of closed cell spray foam when installed well. Generally houses that need an HRV are using interior and exterior air sealing membranes and tapes, and European windows.