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Frost on distribution duct

user-757117 | Posted in Mechanicals on

One of my colleagues today was telling me about how, for the last few weeks, the first three feet or so of rigid duct from the distribution port of his HRV has been covered with a thick (1/8-1/4″) layer of frost.
It has been exceptionally cold here for the last month or so, so I wasn’t terribly surprised to hear this.

I told him that if he was worried about it, he could set the HRV to circulate indoor air for a while until the frost dried up, then wrap the offending length of ductwork with insulation and seal it.

I was thinking of something like pipe-wrap insulation with VB but maybe thicker…
Short of using spray foam, is there a particular product that is designed for this type of application?

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  1. GBA Editor
    Martin Holladay | | #1

    Lots of manufacturers make duct insulation (which always comes with a vapor barrier). Here is one:

  2. user-757117 | | #2

    Aha, thanks Martin.

  3. user-884554 | | #3

    For small quantities, you can even use a "general Insulation/utility insulation/all purpose insulation product". Such products are available at the box stores (as Martin points out, with a vapor retarder) under the trade name Frost King. For the application you are discussing, a couple of rolls and less than $20 will take care of it.

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