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Exhaust venting for oil furnace

alyssa Member Posts: 1
Currently my oil furnace vents into the chimney.  I want to change it and vent the furnace out thru an exterior wall that is located 10’ away.

If I run a 10’ horizontal vent
 ( with a  correct pitch ) and then run a stainless  steel chimney 30’ up the side of the house (with two elbows total) Is this design problematic ?
Will it be more prone to condensation, poor air draft...?



    EBEBRATT-Ed Member Posts: 15,622
    30' up will be fine you will get plenty of draft. Just make sure it is sized properly and installed with the correct material. Combustion test and adjust the burner afterword.

    Why not just put a liner in the existing chimney
  • Robert O'Brien
    Robert O'Brien Member Posts: 3,541
    NFPA31 requires a draft inducer on any horizontal run over 10'
    To learn more about this professional, click here to visit their ad in Find A Contractor.
  • STEVEusaPA
    STEVEusaPA Member Posts: 6,505
    I don’t like it. Probably going to be ugly and most likely problematic with a cold chimney, condensation and draft.
    If you can’t line the chimney, because it’s mechanically unsafe, don’t want to fix it, or want to eliminate it, you’d be better off with a properly installed power venter.
    And depending on your equipment, you may be able to direct vent it.

    There was an error rendering this rich post.

  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 8,094
    Not a fan of outside vent systems. But they are acceptable alternatives with class A venting systems. What will it look like? Can you design an enclosure with proper clearance and use complementary siding to make the enclosure look acceptable? Match the existing siding, or use stucco to offer a masonry appearance. The interior of the enclosure can be insulated to reduce the flue gas condensation issue.

    Make sure there is easy access for cleaning the base of the chimney.


    Edward Young Retired

    After you make that expensive repair and you still have the same problem, What will you check next?

  • SuperTech
    SuperTech Member Posts: 2,186
    Power vent is a much better option, but they require annual cleaning and oiling that a lot of guys overlook. They are also just another thing that could fail or cause problems.  I've been to so many that never had the draft damper adjusted properly, they were installed wide open causing a draft of over -.1" with the barometric damper open fully. Not a fan of power vents and I like direct vent less. I would line the existing chimney if possible.  Its probably the easiest and least expensive option.