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test woodsmoke with oil gas analyzer?

wood furnace with barometric damper is burning at "sweet spot". Can the exhaust be analyzed the same as an oil furnace for excess air & CO content?


  • Charlie from wmass
    Charlie from wmass Member Posts: 4,200
    In theory it could

    but not with the same tool. Burning wood is more of a black art than a science with all the variables you are dealing with. You have species, moisture content, Barometric pressure out doors and in, and water temp around the fire box. It is the only form of heat more hands on than Steam. Enjoy it is a nice heat when done well.
    Cost is what you spend , value is what you get.

    cell # 413-841-6726
  • Pete_in_Jersey
    Pete_in_Jersey Member Posts: 10
    you can still learn something with a gas analyzer,

    but as Charlie from wmass says, there are so many variables that the oil burner combustion relationships don't hold.  You may never be able to get to zero CO, or zero smoke, without running a huge amount of excess air, which wastes energy up the flue.  Even if you adjust it to where you like its performance (how do you do that?) and then analyze the gas, when you change species, moisture content, wood particle size, etc, the excess air/CO/smoke relationship is likely to be different.  But if I had a wood stove and a gas analyzer I'd sure see what I could learn, even if just for curiosity's sake.
  • Charlie from wmass
    Charlie from wmass Member Posts: 4,200
    Analyzers are too expensive

    to use on wood smoke. That is the real issue. Commercial bio energy plants have built in analyzers that do just what you want to do. But muti-million BTU systems that are computer controlled and feeding ground up biomass have larger budgets for controls and can reap larger rewards for the results. That good old rate of return thing.
    Cost is what you spend , value is what you get.

    cell # 413-841-6726
  • Robert_25
    Robert_25 Member Posts: 378
    Baro on a wood burner?

    I would NOT use a barometric draft control on a wood burning appliance.  Burning wood creates enough creosote WITHOUT admitting room temperature air to the flu.  The use of a barometric damper cools the flu gases and promotes creosote formation.  In the event of a chimney fire the baro. will open and feed the fire all the air it needs to destroy the chimney and/or home.

  • kpg2010
    kpg2010 Member Posts: 9

    I would use KOH to check for CO2. I would also check the draft at the breech with the damper closed. You may not need the barometric damper at all. 
  • KOH & CO2 or CO

    what's a KOH? DID u mean CO or CO2.....thanx
  • kpg2010
    kpg2010 Member Posts: 9

    KOH is potassium hydroxide used to measure CO2 levels in the stack.
  • World Plumber
    World Plumber Member Posts: 389
    Particulate matter

    I would not stick my analyzer in there! You'll suck all that fine stuff in and block it up, causing false readings else-wheres possibly ruining the analyzer.
  • Jim Davis_3
    Jim Davis_3 Member Posts: 578
    Wood analysis

    Yes you can use a combustion analyzer to set up a wood appliance.  I have used them on residential and commercial.  Wood and coal are both solid fuels and you can use it on both.  They have filters on them to filter out the debri.

    Controlling draft on wood or any fuel helps make the fuel burn hotter by controlling dilution air.  Therefore you will have less creosote on wood if it burns hotter.  On wood the CO reading is the most critical in the set-up.  It helps establish the under-fire air and the over-fire air, minimum and maximum air.  The lower the CO the more you know you are going in the right direction.  The lower the CO the more complete the combustion and the less ash.  On coal it is less clinkers.
  • further question

    thanx jim. Is it possible to determine the excess combustion air in the fluegas when the woodstove is burning at max efficiency or its "sweet spot"?
This discussion has been closed.