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what to do

drhvac Member Posts: 190
allot of times when checking drafts on furnaces, I find the draft pressure to be higher than it should be. I know ideally we are looking for about a ,-04" draft on a conventional induced draft 80% furnace, but what would you do if the draft was higher? What if the draft was anywhere from - .05 - .15? If you check the sizing of the flue is right, if the gas pressure is right, how do you correct this? Could you put a barometric damper in the flue and adjust it with that? I'm just curious to see what you guys would do if this was your job? Obviously the furnace would work more efficiently if you could slow the combustion gases down where they should be so that more heat is extracted from them. What would you do?


  • JStar
    JStar Member Posts: 2,752

    You got it. Install a draft control damper with a safety spill switch. You should also block off the integral draft hood or remove the external draft hood.
  • drhvac
    drhvac Member Posts: 190

    So a weighted barometric damper would work? Do you do this on your equipment ? I don't know what you mean by this " block off the integral draft hood or remove the external draft hood " Could you explain please? On n induced draft system there is no draft hood, unless your talking about an older furnace with no inducer motor.