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ERV Installation tips?

mikeysp | Posted in General Questions on

Zone 4a.

I am installing a Broan AI ERV in my shop apartment and all duct will be in conditioned space. 

My Heat pump is a mini split; so, the ERV will have its own duct work.

What R-Value insulation should I use on my duct work?

Can anyone explain why my manual says I can use a tandem transition which separates intake and exhaust air by less than an inch; yet, when I install two separate ventilation hoods like I am planning, they need to be 10 feet apart according to the instructions. I was hoping to have them much closer. 

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  1. Expert Member
    Akos | | #1

    That is the difference between an engineered part and spec install. The openings on the dual vent units are design in a way to avoid mixing.

    An ERV is also not like a combustion device, if outside hoods are closer and there is some occasional mixing, it doesn't matter much. My outside vents are about 2' apart and I loose no sleep over it.

    I like the dual vents, they do simplify the install since you only have to cut and flash one one but they can be a bit harder to connect ducts to.

    For the insulation, you only need to insulate the connections from the ERV to outside. The regular R4 stuff works well enough if the runs are not too long. The important part is to tape the sleeve on the insulation to the unit and at the outside hood otherwise you can get sweating on the ducts. The rest of the ducts to the house can be uninsulated as long as they are inside conditioned space.

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