Are back flow dampers needed for intake on ERV?
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I am installing a couple of the panasonic spot ERV’s. One of them will use two matching wall exhaust hoods with the the flapper removed on one for the intake. Should I install a back flow damper just inside of this? Or would this be pointless because any breeze blowing in the duct would be strong enough to open it?
On the second ERV I am installing one of Panasonic’s “Y” combiners that combine both 4″ ducts to one 5″duct and intake/exhaust hood. This is what it looks like.
http://www.amazon.com/Panasonic-FV-WC04VE1-Wall-Styrofoam-adaptor/dp/B003X3HS2Y/ref=sr_1_2?s=hi&ie=UTF8&qid=1454732019&sr=1-2&keywords=panasonic+erv
Would putting a back flow adaptor on both ducts entering this be a good idea (obviously oriented in different directions)? Or are the little flaps on the ERV unit sufficient?
Thanks for any advice.
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Replies
Kail,
If I were you, I would comply with Panasonic's installation instructions. If the installation instructions don't require a separate backflow damper, then there is no need to install one.