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red staining on chimney

I previouly started a thread (#10203) on 12/29/2008 and since then I have new information yet still no resolution. Any help would be greatly appreciated.

During my research I have found I am not the only person with this issue:

1) A local chimney contractor has seen many cases of 'red staining' issues .. he claims it is not the chimney deteriorating but is unsure of the source of the red.

2) Selkirk (a chimney manufacurer) had enough inquiries that they worked with a lab and believe the red is a result of the sulfer in the oil and/or corrosion caused by the sulfer. However even good quality oil has sulfer.

3) I reviewed the web site thread and pursued its leads but got no solution:

primary web site: http://www.heatinghelp.com
specific forum string on topic: http://forums.invision.net/Thread.cf...#Message425748

4) Several major full oil service companies in RI have of yet been able to resolve this issue.

5) Carrier believes it is not there boiler and have tried to wash their hands of the matter.

6) Beckett has seen similar 'red' issues but is unsure how to resolve my problem.

I am actively working with my present oil service company .. they have been very cooperative and want as much as I do to find out how to resolve this issue.

To summarize where I am today, I find small 'black' non-magnetic specs around the smoke pipe a top my boiler and on my roof. The specs location seem to imply they are generated in the boiler and thus eliminate the chimney component. The specs get blown out the top of the chimney flue when the boiler is on, end up on the top of the roof and lip of the chimney and then the morning dew adds enough moisture to leach the red from the spec. The flue cap is not dripping red so this does not seem to be a chimney flue condensation issue.

So .. I am still looking for a solution. The source seems to be the black specs. My thoughts are reducing the sulfer content of the oil or a better burn of the fuel in the boiler might be a step in the right direction. But I am not sure how to do either of these things?

Suggestions are always welcome and thanks for any feed back.

Re: red staining on chimney


I can't verify the source of the red staining, but if you have "black specks a top your boiler/furnace"---you have SOOT!---which means the Beckett burner flame is out of adjustment & must be serviced right away.

An oil-fired burner must be cleaned at least once a year, and the flame has to be adjusted with a COMBUSTION ANALYZER, which is an electronic instrument/probe that is inserted into the hot exhaust gases of the flue pipe---the hot flue gases can be analyzed with the probe for the amount of oxygen, carbon dioxide, carbon monixide & excess air.

A good DRAFT up the flue pipe & up the chimney pipes HAS TO BE MAINTAINED by keeping these pipes hot enough so that the combustion byproducts are carried up the chimney & out of the house.

A separate smoke spot test is used to determine the amount of soot in the flame---varying the amount of air going into the burner & the pressure of the fuel pump & available air in the boiler room, & a good nozzle are all combined to adjust the burner flame for maximum efficiency, minimum smoke, good draft, & a stack flame temperature within proper boundaries---thus, not only will you get a clean flame, but you'll save a lot of fuel by getting a more efficient burn.

Insist that your service person do the flame adjustment using the combustion analyzer---many of them try to do it by "eyeball" & don't even bother to do a smoke/soot test---if they don't have a combustion anlyzer ($2,000), call some other service outfit who does.

Soot is a vicious cycle---it coats the combustion chamber the heat exchanger, the flue breach, the flue pipes & the chimney pipes---it acts as an insulator so the flue & chimney pipes don't get as hot as they should so the needed draft from the hot air rising at the base of the chimney is lost, causing additional soot buildup---so have them clean everything.

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