GBA Logo horizontal Facebook LinkedIn Email Pinterest Twitter Instagram YouTube Icon Navigation Search Icon Main Search Icon Video Play Icon Audio Play Icon Headphones Icon Plus Icon Minus Icon Check Icon Print Icon Picture icon Single Arrow Icon Double Arrow Icon Hamburger Icon TV Icon Close Icon Sorted Hamburger/Search Icon

Community and Q&A

ERV instead of kitchen range hood

88Clayton | Posted in Mechanicals on

Hi, gents.   Kitchen ventilation is not required by code in my city.  But it’s still a good idea to ventillate over a gas range. 

My home will be built tight (oooh, cue scary music), so I’m going to need supplemental ventilation to bring in some air changes.  

If I go with a an ERV (maybe a Honeywell, Panasonic, or Zhender), can I duct a return over the kitchen range in the ceiling and forego the traditional exhaust vent fans?  I’d like to utilize this for bathrooms as well.  

The Panasonic unit I’m interested in is $800-900.   A kitchen range hood vent is ~$2000.   This can make sense from a cost perspective.   But will it work?  Can I have in-demand control of it to turn it on while cooking?  I’m unfamiliar with the technology and how these can be wired up.  

Thank you!

GBA Prime

Join the leading community of building science experts

Become a GBA Prime member and get instant access to the latest developments in green building, research, and reports from the field.

Replies

  1. Malcolm Taylor | | #1

    https://www.greenbuildingadvisor.com/article/two-main-flaws-kitchen-ventilation

    You might want to do a GBA search. Its a topic that gets discussed in Q&A quite frequently. There has been some good debate.

    1. 88Clayton | | #3

      Thanks. I’ve read Alison’s article before. Good information about vent hoods. Not much about ERV/HRV approach on there.

      I know it may not work for a kitchen exhaust, but seems like it could work for bathrooms while also being able to provide makeup air for a tight house. I just don’t know how the controls would be configured… Is it on a switch, a sensor?

      I’m mainly trying to avoid the need for having supplemental air brought into the house *and* bathroom fans, *and* kitchen exhaust. I also see problems with a supply only ventilation. Just seems like a sloppy approach when I’m trying to control the indoor air in a way that makes sense. I don’t want to depressurize the house, but I don’t want to oversupply the fresh air either.

  2. Trevor Lambert | | #2

    What you're suggesting won't work, for several reasons. In order to get a reasonable capture rate, the return would need to be very close (like 18-22") to the cook top, and it would need to have a hood too. You would also need a lot of air flow, probably over 150cfm. That's more than your whole house ventilation requirement will be. Lastly, you're going to foul up your duct and possibly your ERV core. The typical recommendation from HRV/ERV makers is that the kitchen return should be at least 6' or more away from the cook top for this reason.

    Zehnder makes an integrated range hood for their HRV systems, which includes a bypass such that when you run the range hood all the other returns are closed. Two problems with this system is it's reportedly extremely expensive; I wasn't able to find an actual price, but this opinion was put forth by a Zehnder representative. If they think it's very expensive, I think it's fair to say this device is well over $5000. The second, bigger problem, is unless you live in select European countries, you simply can't buy it. I made multiple inquiries to different divisions of Zehnder and got nowhere.

    One option that may actually be possible, if planned for at the design stage, is to have a standalone HRV dedicated to being the range hood. Buy a cheap range hood, ditch the internals and hook it up with the HRV. You'll need some good filtration to protect the HRV core. I might have done this if I could start over again, just I don't have room for such a thing. (HRV is the better option than ERV for this application).

    ERV returns in the bathrooms is standard practice.

    1. 88Clayton | | #4

      Good idea. So the same unit hidden behind the hood would be ducted for my supply?

      Can an HRV of this size even pull 150-250 cfms? It’s possible that a gas range may call for a higher CFM in their specs. Although, I’m trying to stay under 400 CFM.

      1. Trevor Lambert | | #7

        No, the HRV would have to be located outside of the hood; not even close to enough space in there. Either in another room, or in bulkhead in the kitchen. If I was designing my house again, I might put two HRVs side by side in the utility room, one for the general ventilation, one ducted directly to a range hood.

        1. 88Clayton | | #9

          That sounds cool.

  3. User avatar
    Stephen Sheehy | | #5

    We have a recirculating hood that we literally never use. The hrv exhaust in the kitchen is located about eight feet from the induction cooktop. When we're cooking we usually hit the boost switch. We' re serious cooks who cook a lot, but not stuff that generates lots of smoke. It all works fine. No hole in the wall for the vent is a plus.

    If you haven't tried induction, buy a cheap one burner unit and try it out. I don't know anyone who wants gas after using induction. It's faster, more energy efficient, just as controllable and you aren't dumping water vapor and CO2 into your house. You also don't need a propane tank or a natural gas hookup.

    No bathroom fan. The hrv boost takes care of shower moisture.

    1. 88Clayton | | #6

      Sounds appealing.

    2. Trevor Lambert | | #8

      Stephen, have you monitored air particulates during and after cooking? You can't go by smell. I have the same setup as you, and any amount of cooking shoots the particle count up for the whole house for several hours afterwards. The recirculating hood doesn't help, and neither does running the HRV on boost mode. Our boost mode bumps the airflow from 90CFM to over 250CFM, and the effect it has on lowering the particle count is negligible.

      1. User avatar
        Stephen Sheehy | | #10

        Trevor: I haven't monitored particulates at all. Ignorance is bliss?

      2. Malcolm Taylor | | #11

        Trevor,

        Yet another thing I don't know half as much as I should about.

        In the absence of gas cooking and combustion, do you know what proportion of the fine particulates generated by cooking any food are harmful? I can't get any sense if it is all or just some.

        https://newscenter.lbl.gov/2013/07/23/kitchens-can-produce-hazardous-levels-of-indoor-pollutants/

        1. Trevor Lambert | | #12

          I don't think it matters what the particles are composed of at the PM2.5 size range. I'm no expert, I'm just basing that assumption on the fact I've never seen any mention of disambiguation of particle type in any of the literature on air quality.

Log in or create an account to post an answer.

Community

Recent Questions and Replies

  • |
  • |
  • |
  • |