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What is best thermometer to measure stack temps?

Post in 'The Hearth Room - Wood Stoves and Fireplaces' started by John Ackerly, Apr 6, 2013.

  1. John Ackerly

    John Ackerly Member

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    I'm looking for an affordable, but more professional thermometer to measure flue gases in my stack. Unfortunately, my pipe goes up my chimney 6 inches above the stove, so I'll have to insert the thermometer pretty much right as gases leave stove. I'm assuming that you don't want temps above 350 for too much of the burn cycle if you are looking for high efficiency. And, you don't want them below 300 for too much of the burn cycle either, or else you are flirting with condensation. I hoping to get this thing in and still have a few weeks to use it before end of heating season.... Any recommendations appreciated. Thanks.

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  2. begreen

    begreen Mooderator Staff Member

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    That is going to be a tricky location. Are you talking single wall pipe? If so, you want a magnetic, surface, flue thermometer like the Condar Chimguard.
  3. rideau

    rideau Minister of Fire

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    In addition, any thermometer mounted on the pipe that close to the stove top is going to pick up some heat from the stove top, affecting the reading. Still, a magnetic thermometer placed there will give you information about what is going on inside the flue. There is a thread back in January, entitled "Anyone have a pic of a stovetop thermometer.." which gives info about some very good stovetop thermometers, with prices and where to purchase.
  4. begreen

    begreen Mooderator Staff Member

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    You might try putting the thermometer on the horizontal connecter to the thimble and see how that works.
  5. fossil

    fossil Accidental Moderator Staff Member

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    On my shop stove single wall, I run a magnetic thermo placed just above the flue collar. I don't think it matters much where you put it, you'll learn how it behaves indication-wise as you operate the appliance. Rick
  6. John Ackerly

    John Ackerly Member

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    Yes, its single wall pipe. I have magnetic thermometers to read the tempurature of the top of the stove, but I am really curious abut the actual temp of the flue gases. I hope they are higher. I also have a thermocouple measuring temp of stove top, and that reads under 300 degrees most of the time. I'll check out that thread.
  7. Dr. Richards

    Dr. Richards New Member

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    Central ME
    Auberins wood stove digital probe thermometer. Love mine. Works great, accurate.
  8. mellow

    mellow Resident Stove Connoisseur

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  9. ddahlgren

    ddahlgren Feeling the Heat

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    Without a probe you are just playing around. Why in the world do you care what the paint temperature is on the flue pipe. Creosote forms on the inside not the outside of the pipe. I did a bunch of testing on a Rutland magnetic temp sensor and have a thread here with detailed results and it was off 3X compared to the probe. I can not imagine the others built much differently to be honest and qualified the Rutland in boiling water to be correct at least at 212 though off quite a bit at room temps.
  10. BobUrban

    BobUrban Minister of Fire

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    They are all just a bench mark at best unless you go with a high dollar job like a Tel-Tru. I just want to know a close proximity of what is going on and do not care to be exact to the degree +or- 20 or so degrees means nothing if you are in the range you like. I say get a magnet job and stick it to the outside - or move the one you have up there for referrence and save the drilling of a hole in your pipe. Other opinions will vary.
  11. oldspark

    oldspark Guest

    Just playing around huh, have used one for a guideline for over 30 years and continue to use them with out any problems with never an over fire or creosote issue, please dont post misinformation for the new people on here that dont know any different.
  12. 3fordasho

    3fordasho Feeling the Heat

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    This... All though I would not consider my $20 Tel-Tru to be high dollar. I've used them on two stoves and am convinced of their accuracy and reliablity. This one will work:
    http://www.teltru.com/p-272-big-gre...ter-lt225r-5-inch-stem-2001000-degrees-f.aspx


    Just don't exceed the 1000f limit because they don't like it .. trust me;-)
  13. remkel

    remkel Minister of Fire

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    I would avoid the ones that read in Kelvin... The conversions are a pain!
  14. charly

    charly Guest

    100_6371.JPG 100_6375.JPG 100_6380.JPG Tempoint, easy recalibration as well.

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