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soot problem

chevy03 Member Posts: 2
I came across a weil mclain oil burner that had not been used all summer and when first started smoked out the house . Inside the fins,chamber, and flue there was a yellowish tint in with the soot and it was all blocked up. I was wondering if anyone knows what could have caused that.


  • chevy03
    chevy03 Member Posts: 2

    Also it seemed like it was possibly wet at some point maybe from condensation in the boiler but that doesn't explain the yellow in the soot.
  • Steamhead
    Steamhead Member Posts: 14,466
    edited September 2009
    That's sulfur

    which means this boiler hadn't had proper servicing in a while. Sulfur content in fuel oil is going down.

    If this is a 68-series or early Gold boiler, and doesn't have an electronic primary and solenoid oil valve that will provide valve-on and motor-off delay, you should add these features. They will help keep the boiler from plugging up in the future.
    All Steamed Up, Inc.
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
  • Jim Hankinson
    Jim Hankinson Member Posts: 99

    It's not all that unusual. The boiler sits all summer sweating and some of the moisture soaks into any residue left from the heating season. When the burner is started up the boiler's cold, the chimney's cold and as the wet debris starts to dry it also expands a little, kind of like popcorn,

    I hate cleaning heat only boilers after they've sat for a couple of months idle. It ruins brushes, clogs the soot snoot and in general is just a mess.
  • Jean-David Beyer
    Jean-David Beyer Member Posts: 2,665
    cleaning heat only boilers

    "I hate cleaning heat only boilers after they've sat for a couple of months idle."

    Why do not heating contractors do annual service at the end of the heating season instead of at the beginning? Then they could clean out stuff before it has sat around for 3 or more months turning to stone or goo. I asked my latest contractor that and they said it was because that is when they were doing their pre-summer air conditioning work.

    It seems to me that the best time for me (as a customer) is in mid-April, before their A/C work begins even though the heating season around here is not always over by then. I can turn the boiler off the night before so they do not burn themselves while working on the unit.
  • Paul Fredricks_3
    Paul Fredricks_3 Member Posts: 1,549

    We try to do all our cleanings in the spring and summer. The biggest problem is that a lot of customers resist having it done at that time. Then, when the weather starts to turn, they all call for a cleaning and we get backed up till February. Then they get mad at us for not being able to do it this week. Every year. And believe me, we try as hard as possible to get them to do it early.
  • Edward A. (Ed) Carey_3
    Edward A. (Ed) Carey_3 Member Posts: 236
    edited September 2009
    Paul is correct

    Paul is correct.


    When I was still in the field, (now retired to be one of those old consultants), I used to mail cards out to my clients, (about 5000 of them) almost begging with early season discounts to get them to do annual tune ups on oil boilers and oil heating equipment early in the season.


    Amazing how many of them simply would not do it. They played into human nature, and would not respond to the needs of their heating system until the weather got cold and they HAD to.


    Any cold start or heating only boiler should be operated for several days before it is opened and cleaned, or you will clean the muck out now, and be back a week or two later removing the remaining soot that has swelled and has partially blocked the flu passages.


    I like Jim's "popcorn" analogy. It is very descriptive and absolutely correct.


    Ed Carey  
  • Dan C.
    Dan C. Member Posts: 248
    low limit

    So if you have a boiler that is maintaing all summer long to satisfy a low limit for a tankless that is no longer being used, is it a bad idea to shut off the boiler when not being used and not waste the oil? 
  • Leo_36
    Leo_36 Member Posts: 8
    Staying Clean

    The Weil Mclain 66 and 68 series along with the Peerless JOT/TW boilers were the worst.  I do the majority of the tune ups for my company and when I see one of these off I wish I stayed home that day.  Some are so bad they need to be water washed.  They can take up to three hours to do.  We charge extra for a tune up after a certain amount of time so the customer really doesn't save much.  If they are done in late spring or early summer they can build up moisture over summer which losens the junk making a plugged boiler very likely.  Again another service call.  The best is to set the  low limit to 120 or make it a cold start and add an indirect which will make the burner fire periodically.  Warmthmakes for a clean boiler in this case.

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