"Dead" chimney with oil furnace

Discussion in 'HVAC Heating & Cooling' started by kim156, Mar 17, 2008.

  1. kim156

    kim156 New Member

    Messages:
    4
    I've been having problems for about a year with my oil burning furnace. The furnace is only 5 years old. Starting last year I was having to continually push the reset button to get it to fire. Then it went to not working at all. I have had the repairmen out about 10 times over the past 12 months and they finally replaced a part (forgive me I don't remember what) so that now it runs and heats. However there is a lot of soot and it's quite loud. I had the repairman out again today and after running several test he determined that the problem is a "dead" chimney and not a cracked heat exchanger.

    He admitted he's only seen this problem about 3 times over the past 12 years so I'm a bit skeptical. I don't want to have to pay $1200 for a new chimney liner if it's not really going to solve the problem. Does anyone have any words of wisdom? :(
  2. Cookie

    Cookie .

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    5,658
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    .
    Yes, always keep a record of what is being fixed when the repairmen comes. Is their maybe a warranty?
  3. kim156

    kim156 New Member

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    Yes - it is under warranty but the furance only. The chimney issue would not fall under warranty......
  4. Bill Arden

    Bill Arden Computer Programmer

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    Location:
    MN, USA
    I have never heard of a chimney dieing. It could be plugged, or broken, but dead. I did not know that live ones existed. ;)
  5. krow

    krow Plumber

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    Location:
    Ontario, Canada
    I heard that term before, and the tech that explained to me was referring to the brick/inner wall collapsing/ flaking.
  6. Wrex

    Wrex New Member

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    Location:
    New Jersey
    Chimneys are supposed to be lined (unless your house is really old) since its required by code for newer homes.

    For example in my house built in the 50s is lined with terra cotta.

    If your chimney is not lined then flaking bricks and internal blockages of that sort are possible however if your chimney is lined then you may just have some sort of buildup.
  7. yarrow

    yarrow New Member

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    11
    Location:
    Washington
    Your problem is that you now have a much better/more efficient system.

    the new furnace burns hotter/cleaner, which then releases much hotter gases into the chimney, which then react with the soot/creosote buildup from the previous less efficient furnace. it's basically cooking the residual buildup in your chimney. it can also cause sweating in the chimney, also not a good thing, as it will eventually erode the chimney.

    installing a liner will take care of this. i suppose you could sign on for a heavy duty chimney cleaning, but i'm not sure that you'd ever get enough of the older buildup off to completely prevent this reaction.

    a liner is good for other reasons, especially in older homes - as the mortar in older chimneys begins to age, small fissures can occur, allowing smoke and gases such as CO to escape into your living space.
    Last edited: Mar 26, 2008
  8. BigLou

    BigLou New Member

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    138
    ok the only part you kinda sorta got right is the sweating or more properly condensation, which is acidic and can degrade the chimney with time.
    A newer more efficient unit will release COLDER flue gases in the chimney which can cause draft issues. there is no cooking of any sort taking place.
    Creosote also only builds up from wood fired appliances

    Umm unless I am losing my mind a good cleaning will take more then enough of any build up out. Seeing as its soot which will just fall off at the slightest provocation. If you don't believe me take off the old smoke pipe and bang on it a few times.
    Well I guess this is true but not very probable unless the home has now been made air tight. If anything the hot gasses rising or even just got air escaping from your house are going to suck in air through the cracks like a venturi

    Installing a liner will constrict the colder flue gasses allowing them to stay hotter longer and pull a draft in the chimney. I don't think a chimney can die. If your heating guy does not have a basic understanding of how his appliances work and how they draft then I would be looking for a new tech. Most new furnaces will state that they require a liner right in the installation instructions.

    My guess is its in the burner and has nothing to do with the chimney or the furnace it self
  9. yarrow

    yarrow New Member

    Messages:
    11
    Location:
    Washington
    sweating or more properly condensation, which is acidic and can degrade the chimney with time. exactly

    A newer more efficient unit will release COLDER flue gases in the chimney which can cause draft issues. there is no cooking of any sort taking place.


    hmm. i had been told otherwise from our chimney and hvac guys when we were having a similar problem, but perhaps i'm misunderstanding what was actually causing the culmination of soot buildup/fallout at the bottom of the flue. they both mentioned seeing this problem on other occasions (since folks always upgrade to more efficient systems, not the other way).

    so if it isn't because the new system is burning hotter (e.g. releasing less particulants thru cleaner, hotter burn) and reacting with the chemical sludge on the chimney walls, then is it the condensation that causes the soot to collect at the bottom in these cases after a new system has been in operation for a period of time?

    Umm unless I am losing my mind a good cleaning will take more then enough of any build up out. Seeing as its soot which will just fall off at the slightest provocation. If you don't believe me take off the old smoke pipe and bang on it a few times.

    and if you stick your hands inside, they'll always come out black. yes, you'll get the lion's share of it, but never all - which may be fine, but i'd still do the liner route.

    Well I guess this is true but not very probable unless the home has now been made air tight. If anything the hot gasses rising or even just got air escaping from your house are going to suck in air through the cracks like a venturi

    i've lived in two converted mansions that were made into apartments in which the landlords finally had to stop allowing fires in the fireplace - you could smell the smoke coming out of the exposed sections of the chimney, in the closets that backed up to the chimney. old house, old windows - but maybe strong enough drafts enough to cause backdraft thru the brick/mortar?
  10. Wrex

    Wrex New Member

    Messages:
    126
    Location:
    New Jersey
    If you do decide to have the chimney lined there are many ways it can be done including a cast in place process however this method is irreversible and if the opening is made too small you can have other problems that may make require complete destruction of the chimney.

    So you must make sure that the person performing this task knows what they're doing.

    Another easier (and cheaper) process is inserting a stainless steel liner.

    However if your chimney has annoying bends they do make some liners flexable for this purpose however it could extend the time needed to complete the job. If you hire someone to do it though it should be a quick and painless process.

    When installing a stainless steel liner you want to make sure that its as wide as your chimney will accept the wider the liner the better the draft.
    Last edited: Mar 27, 2008
  11. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Messages:
    22,324
    Location:
    New England
    Depending on the technique used, the flue gasses are often very cool - for maximum efficiency, the systems pull as much heat out of them as possible. Those that do this are called condensing burners - to gasses are so cool that you can get substantial liquid water out of the flue gasses, and need to drain it away. A condensing burner often used plastic PVC pipe as the flue. that type of burner requires a condensate drain. The next stage down in efficiency is something in the mid-80% range, where they've extracted some heat, but not as much...the gasses are still cooler than the old stuff, but can condense on their way outside in an uncontrolled manner if the flue is not designed properly. This type often specifies a stainless steel flue pipe. Once you get even lower in efficiency, more conventional flues can work. I think that is what is happening in your case...the gas, laden with exhaust products (of which a substantial portion is water vapor) is cooling off, not drawing up and out of the flue well. The condensation can really wreck a brick and mortar chimney fairly quickly...literally eating it up.
  12. kim156

    kim156 New Member

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    4
    chimney -furnace update

    Hi;I had the proffessionals clean and inspect my chimney {sat. afternoon};they removed about 1 quart of soot from thechimney and put a 500 watt light at the bottm ;took dig. pics. ;CHImney Is Fine!!.They found some minor flaws at the basement level...they are going to patch a couple minor areas at the pipe entry area with re-factory cement.O.K. now that we know the chimney is good...we are back to the furnace;I should mention its a CARRIER normal efficiency 80% unit.Remember I have had 10 visits by htis companies tech's some have mention possible faulty heat exchanger??I have the sooting issue in my house;[my filters were black after one month] any help would be appreciated.The last tech was the service manager;he is reluctant to trouble the CARRIER rep, about my problem...after a year I think its time!
  13. Bill Arden

    Bill Arden Computer Programmer

    Messages:
    584
    Location:
    MN, USA
    Q1: Did the furnace ever make a really loud bang or a loud roaring sound after you pressed reset?

    There is a chance that this earlier problem could have damaged the heat exchanger.

    You should buy a CO(Carbon Monoxide) alarm.

    Q2: Do you have a gas hot water heater or anything else connected to the chimney?
  14. kim156

    kim156 New Member

    Messages:
    4
    Yes ;....the furnace did do bangs..and sounded like a freight train some times at start up;even after some tech work.The furnace is the only thing on the chimney
    Last edited: Mar 30, 2008
  15. Bill Arden

    Bill Arden Computer Programmer

    Messages:
    584
    Location:
    MN, USA
    Buy a CO(Carbon Monoxide) alarm! :eek:

    I had my furnace do that and then it blew soot out the fire door. :eek: Luckily for me mine is a very old heavy unit (Sears 10) and my heat exchanger was fine.

    Newer furnaces use thinner metal to improve efficiency.
  16. BigLou

    BigLou New Member

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    138
    Kim,
    RANT
    thats a LOW efficiency unit and in my personal opinion they should be out lawed here in the states like there are in so many other countries. nothing normal about running such low efficiency equipment. The only good news is that rules out your chimney its pretty hard to not get flue gasses that hot to vent.
    /rant

    Kim,
    I think its was time after the 2nd or 3rd trip. Now its time to fire this company and get a knowledgeable person in there to fix your problem. Have they charged you for all ten visits ? your local heating supply house should be able to point you in the right direction on who is good. My neighbor is an oil burner tech, he never took more then one trip to fix anything that was wrong with my 60 year old boiler before I replaced it with a new gas unit.
    I think your person is afraid to call the rep and admit their incompetence.
    When I did find some one was able fix it I would sue the first company for your money back. Seeing as you at least paid them for the first service call and they never fixed your problem. Saying it had a dead chimney is like a mechanic telling some one they have stale air in their tires of they need to change the head light fluid. Really makes me wonder about the ethics of this company and how many other people they are fleecing out of thier money

    All oil fired units consist of two seperate parts often manufactured by two seperate companies. The furnace it self and the burner which has the reset button you have to keep pressing. My personal guess is the burner was over firing which overheated and cracked the heat exchanger.

    Lou
  17. BigLou

    BigLou New Member

    Messages:
    138
    Kim,
    thats almost defeniatly the transformer that sparks the burner which is where the reset button is located. when it fails to ignite for a shot time unburnt oil is sprayed in to the firebox and when it does finally ignite BOOM and soot goes everywhere. Thats oil heating 101. I missed this post when posting my last reply and would like to make this my cause for a damaged heat exchanger

    Lou
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