In loving memory of Kenis D. Keathley 6/4/81 - 3/27/22 Loving father, husband, brother, friend and firewood hoarder Rest in peace, Dexterday

OWB Shop Heater

Discussion in 'OWB's and Gasification Boilers' started by lukem, Jun 5, 2025.

  1. lukem

    lukem

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    After all these years I'm FINALLY ready to hook the OWB up to the shop. Any recommendations on heat exhanger / fan units? I'm heating about 1,000 sq ft of moderately insulated space.
     
  2. yooperdave

    yooperdave

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    Anything on craigslist or marketplace near your area?

    What inside temp are you hoping to get?
     
  3. lukem

    lukem

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    Nothing good for sale used.

    I only want to be able to keep it 60 degrees on a 10 degree day. Any warmer inside or colder outside in probably going to find something else to do.
     
  4. Horkn

    Horkn

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    Are you thinking like a modine style heater? Just not needing any heat to be made in the unit, just a heat exchanger with a blower?
     
  5. yooperdave

    yooperdave

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    Exactly.
     
  6. Screwloose

    Screwloose

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    I know amateur cutter has some in his shop. I have seen some really nice systems made from vehicle radiators. The older style with flanges on the side makes it easy.
     
  7. brenndatomu

    brenndatomu

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    Beat me to it... I've seen some very affective shop heaters made up of an old car/truck radiator with a box fan zip tied to it, on/off controlled by one of those stand-alone 120v thermoswitches :yes:
     
  8. Horkn

    Horkn

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    Right? Why overcomplicate things. That would work great.
     
  9. lukem

    lukem

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    I've considered making my own, but honestly don't really have the time or energy to find the right mix of radiator surface area and airflow to deliver the right amount of BTUs per hour. Calculators say 50K BTU will be more than plenty...and I'd rather have a small unit that runs a lot than a big unit that cooks you for 1 minute then freezes you, and repeats. I'd rather spend a couple extra bucks and pull something out of a box and run it.

    I do know I'm just going to run a wifi plug with a thermostatic plug sitting on top of it. That way I can turn on the heat in the morning from my phone to warm it up.
     
  10. lukem

    lukem

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    Still need to plumb it in but that's easy. Past experiences tell me I need to be able to bleed air so that's why I went with those 90s.

    The thermostat location is probably too high, but it will still work and look at little cleaner.

    PXL_20250826_154341104.jpg

    PXL_20250826_154312464.jpg
     
  11. lukem

    lukem

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    Looks like its going to get cold enough this weekend to actually turn this thing on. Curious to see what it can do. I've ran it a few times for a few minutes and it seems like it puts out plenty of heat. I'm only looking to keep it about 60* in there when I'm working and 45 when I'm not.
     
  12. lukem

    lukem

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    It was about 20 degrees this morning and I took the shop from 43 to 62 in under an hour. That's good enough for me. Definitely cycles the boiler more though. Oh well, firewood grows on trees.
     
  13. Horkn

    Horkn

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    Well, you're putting it to a good test now. Is it supposed to get colder tonight for you in Indiana? This am was shock here in Wisconsin.
     
  14. lukem

    lukem

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    It was supposed to be 10 here last night but only got down to 20. Forecast is 7 for tonight.