Click here to Find a Contractor in your area.
In fairness to all, we don't discuss pricing on the Wall. Thanks for your cooperation.
Need to contact us? Visit

80%+ vent terminations in cupolas

bob youngbob young Member Posts: 2,174
WHAT does manufacturer recommend


  • TimcoTimco Member Posts: 2,814

    So I have a water heater & Furnace both 80% condensers with fan assist. Each terminates into a different cupola. The water heater has a steady stream of clear water come back down from the chase when it runs and the furnace has the classic green oxidized water streaming back.(copper cupolas) Should these terminate outside and not into the cupolas? WH is run in ABS and the furn in sch 40.

    Working on steam and hot-water systems isn't rocket's actually much harder.
  • dondon Member Posts: 66
    What is

    What is a cupola? TIA.
  • TimcoTimco Member Posts: 2,814

    MFG says in manual to terminate outside, no mention of cupola. I will have to call. Cupola is a box on the roof to hide pipe terminations. These are copper...

    Working on steam and hot-water systems isn't rocket's actually much harder.
  • leelee Member Posts: 458

    Think old barn, the thinga t the top. Usually had weather vane mounted to it.
  • bob youngbob young Member Posts: 2,174
    termination point

    i think you might have answered your own question, Tim. if the air is restricted sh*t happens----sometimes lol what say tim mcelwyn, the gas expert.

  • I'm picturing an enclosed copper copula, capped with openings or louvers on the sides. It sounds as though the warm/moist "exhaust" is hitting and condensing on the inside of cold copper and then dripping/running back down.

    Possible "cures" -

    1.A drip pan like they have under air conditioning condenser coils and pipe the condensate away.While it could be made to work I don't see this as practical. A lot of work plus it's very likely to freeze/plug in winter.

    2. Insulate the inside of the copula so the warm exhaust would escape before condensing. (Might work?)

    3. Run the exhaust piping out the side of the copula. (Pick the pitch less visible. (Also think prevailing wind direction -I'd also insulate the exhaust where is runs through the cupola.) Probably #3 has the best chance of working. I'd discuss it with the manufacturer and see what they suggest /recommend.

    It looks like one of those jobs you want to walk away from.
    If you can fix it, you're a hero. If it doesn't work (and the odds favor this) you get all the wrath /frustration of the owner who wanted the "cute cupolas" and NOW thinks it's your fault they don't work.

    Is running a "normal" exhaust installation not viable?

    - Rod
  • TimcoTimco Member Posts: 2,814

    Thanks for the ideas. #3 is my plan, and Wednesday I will measure runs & count 90's then call mfg. I like being the hero so I will take this on...

    Working on steam and hot-water systems isn't rocket's actually much harder.
This discussion has been closed.


It looks like you're new here. If you want to get involved, click one of these buttons!