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Community and Q&A

Filter box for ERV outside air duct

pnwbuilder | Posted in General Questions on

I am planning to install Panasonic Intelli-Balance 100 ERV in my new house and am contemplating to include an inline filter box in the outside air supply duct in addition to the build-in one. I believe Matt Risinger had interviewed Panasonic salesrep at one of the shows that recommended this. I am looking for some suggestions on whether this is a good idea and how this can be accomplished. I think a filter box like this would work for my system, but I am puzzled by how to insulate it and make vapor proof to prevent condensation. I am in climate zone 4 Marine, condensation will be only a consideration during heating season.

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  1. alex_coe | | #1

    Following this thread as I'm thinking the same thing.
    I just bought 2 of these ERVs. You're going with the new revision with the added boost switch capability right? FV-10VE2? I ordered 2 units as soon as I saw that. Great product and value.

    1. pnwbuilder | | #2

      I didn't buy mine yet, but most likely it will be the new version. Where did you buy yours from?

      1. alex_coe | | #8

        I'm in Canada. My retailer was SupplyExpert.

        You definitely want the updated version. The boost function is key. Here's how I plan to run mine. Fans constantly running at low CFM for quietest operation. Exhaust point in bathroom instead of bathroom fan. TP Link smart wifi switch in bathroom connected to boost function on the ERV. This way you've got a switch in the bathroom to boost up to 100%, but can also turn the boost on/off from your phone via the app or Alexa/Google Assistant devices.

  2. exeric | | #3

    I have the earlier version of the Panasonic and I've bought a very similar filter box from the same outfit. But man, the price of the HEPA filter for your box seems high. I'm afraid I may be just too much of a scrooge for that. I got the cfb-6 model filter box. I think you might find it more economically viable over the long haul if one replaces the filters every 3 months. The cfb-6 can be purchased with MERV 15 filters, which aren't too bad, at least compared to the HEPA filter.

    I got MERV 13 filters and a set of carbon filters just for fire season around here.

    1. pnwbuilder | | #5

      Eric, could you please share the details on how you've plumbed the filter box in your system. I am struggling to understand how to get it into the outside air supply line and make sure it is properly insulated and won't be a cause for condensation. I wonder if I would've been better off running ERV outside supply/exhaust ducts outside of the conditioned space.

      1. exeric | | #6

        I used R8 insulated flexible duct in the attic buried under cellulose and also from the ceiling duct junction to the outside air inlet of the ERV. The filter box itself is not insulated and that can be a potential problem depending on your climate. In my climate I just decided I didn't need to worry about it.

        1. pnwbuilder | | #7

          Thank you for the update. I'll see if I can shuffle things around a bit to make it less prone to the condensation issues.

  3. pnwbuilder | | #4

    Yeah, the HEPA filters are expensive, but they last more than 2 years according to their website. Only the MERV 11 filter needs to be replaced every 3 months. It is also possible to omit the Hepa filter by installing a spacer instead.

  4. qofmiwok | | #9

    Anyone do this? How did you insulate it? My Zehnder only has Merv 13 and I wanted this in line box that I would put a Merv 15 in for 4 weeks a year we get forest fires. I put it in line today but just realized I missed the condensation issue... duh. I should have put it in line *after* the ERV.

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