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Lots of white smoke from neighbor's chimney

No other chimney in the neighborhood belches such smoke, which is probably condensed water, because it vanishes. But I'm wondering if there's a problem with their heating system, for instance: with a water-based system, there could be a hole in the heat exchanger, spurting water into the combustion chamber, causing steam? This is the second year now that I notice this about that chimney, every morning when the weather is cool.

Comments

  • Jamie Hall
    Jamie Hall Member Posts: 23,168
    Most likely.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 15,453
    is it oil or gas? Gas will look like white smoke when it is cold outside as the flue gas condenses.
  • ChrisJ
    ChrisJ Member Posts: 15,588

    is it oil or gas? Gas will look like white smoke when it is cold outside as the flue gas condenses.

    I get some white smoke when it's really cold out. Near or below 10F
    I don't think I notice it if it's in the 20s out though.

    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • meofbillions
    meofbillions Member Posts: 2

    is it oil or gas? Gas will look like white smoke when it is cold outside as the flue gas condenses.

    Why would fuel type matter? A water leak into any combustion chamber would produce steam.
  • bburd
    bburd Member Posts: 909
    edited October 2022
    Gas fired systems produce visible water vapor in the exhaust whenever it’s very cold outside. Oil fired systems don’t, or at least not until it’s a great deal colder, unless there is an internal leak in a steam boiler above the waterline. The difference is due to the much higher hydrogen content of gas, which produces more water vapor in the products of combustion.

    Bburd
  • Steamhead
    Steamhead Member Posts: 16,796
    If it's a steam system, the boiler probably has a leak above the waterline.
    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
    Consulting
  • mattmia2
    mattmia2 Member Posts: 9,575
    Could it be a condensing boiler or furnace using the chimney as a chase?
  • HVACNUT
    HVACNUT Member Posts: 5,804
    @meofbillions, is your neighbor even aware?
  • Jamie Hall
    Jamie Hall Member Posts: 23,168
    Quite true that a gas fired boiler or furnace will produce some white smoke -- but not a lot of it. If it's lots of white smoke, it's a leak.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • MikeAmann
    MikeAmann Member Posts: 996
    bburd said:

    Gas fired systems produce visible water vapor in the exhaust whenever it’s very cold outside. Oil fired systems don’t, or at least not until it’s a great deal colder, unless there is an internal leak in a steam boiler above the waterline. The difference is due to the much higher hydrogen content of gas, which produces more water vapor in the products of combustion.

    Just to add to this - if you burn 20# of propane, say with a tank-top heater, you have just put 4 gallons of water into the air.