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Can anyone tell me what this is dripping down the chimney wall in the basement?


  • newagedawnnewagedawn Member Posts: 562
    flue gas condensation, happens when you underfire a boiler or furnace, if its oil fired your stack temp should be min 450
    "The bitter taste of a poor install lasts far longer than the JOY of the lowest price"
  • mercedesmercedes Member Posts: 61
    additional info From the website Engineering Tool box:Stack Temperature
    The "net stack temperature" is the difference between the flue gas inside the chimney and the room temperature outside the burner. Net stack temperatures above 700oF (370oC) are in general to high. Typical values are between 330 - 500oF (160 - 260oC).
    High stack temperatures may be caused by
    undersized furnace
    defective combustion chamber
    incorrectly sized combustion chamber
    excessive draft
    overfired burner
    draft regulator improperly adjusted
    soot formation on the heating surfaces

  • newagedawnnewagedawn Member Posts: 562
    i agree, gross stack 450 minus 70 leaves 380 and the minimum stack is 350, i dont like to push this as what you have is the result, 96 plus systems and other gas boilers or furnaces are different and a whole different type, but from the size of the chimney id bet you have oil fired equipment and those principles apply always
    "The bitter taste of a poor install lasts far longer than the JOY of the lowest price"
  • ChrisJChrisJ Member Posts: 11,008
    Was your setup an oil burner that was recently converted to gas by any chance?
    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
  • GilmorrieGilmorrie Member Posts: 115
    Condensation in the flue can damage the chimney liner. It would be good to have it inspected. Of course, you should have a combustion analysis run and adjustments made.
  • Big Ed_4Big Ed_4 Member Posts: 1,344
    Agree above , but to add ... Most basement chimneys are below ground . If the outside grade looses its pitch away from the house , under heavy rain the water will pool and seep into the chimney .

    I have enough experience to know , that I dont know it all
  • sarahm73sarahm73 Member Posts: 27
    Ok so here's the thing... I moved into this rented house in Sept '15 with my young kids. Last week we returned home to an odd smell. I opened the basement door and saw smoke billowing up the stairs. A minute later the smoke detector of my duel alarm activated. I evacuated and called 911.
    The fire dept traced the smoke to the furnace and red tagged it. They were perplexed by the CO alarm not sounding as the levels were high enough. They brought in fans to clear out the CO until the level were eliminated.
    The following day the fuel comp arrive to assess. The workers told me that the chimney was completely blocked by fallen bricks and soot and that no gases could escape.
    The chimney guys came to assess and said the chimney looked like it hadn't been cleaned in decade. There was no liner or cap. The cement had turned to sand.
    Per the tags hanging on the furnance downstairs, it looks to have been installed in 2000. Evaluations were done regularly but as for cleaning and servicing tags? There are 5 of those from 2000-last week.
    Here's the kicker, before I moved in I had mild asthma. In oct 2015 and Oct 2016, after I just started to use the oil heat for the season, I had very severe attacks leading to about 8 days hospitalization in total. In march I got up in the middle of the night and my legs went from under me. Not sure if I fainted but it's never happened before. My kids have had frequent headaches and nausea (dr was monitoring as no apparent cause).
    I'm just piecing it together now but I think we were exposed to low levels of CO for a long time! I'm horrified.
  • sarahm73sarahm73 Member Posts: 27
    ChrisJ I'm am completely inept when it comes to home heating mechanics but from what I can gather the furnace is definitely oil. The Heating System Evaluation tags say the water the water is heated by gas. Oh also from 9/'14 to 5/'17 there was no System Evaluation or oil burner cleaning done. I have no idea if or when the chimney was cleaned ever. Certainly not since I've been here but the chimney repair guy would bet it's been a VERY long time if ever. The house was built in 1890!
  • Tim McElwainTim McElwain Member Posts: 4,365
    This is a totally unacceptable situation shut the unit off and get professional help to evaluate the safety of the unit.
  • sarahm73sarahm73 Member Posts: 27
    I agree. I'm looking for a new place as I will never trust the landlord again. I'm shocked at the level of neglect. I'm considering taking legal action. I've been constantly ill for the last two winters. I'm so thankful my kids were in school during the day and with their dad a few days a week. It should never have happened though and I think the landlord should be held accountable.
  • captaincocaptainco Member Posts: 451
    Legal action may be good before someone else actually dies! Landlord abuse is widespread..
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