Candles and sooting

Guy_5

How many of you have had issues with soot and scented candles? I have had several people over the years pointing fingers towards the boiler, when the culprit actually the candles.
The dark soot clings to the cold carrying structure, clearly outlining the studs, nails, etc. I have found it most prevalent in the upper corners of the rooms.

Alan R. Mercurio

It's a very common problem

If you have not read this I think you'll appreciate the article. It's helpful to show the customer so they have a better understanding how this happens and that it is in fact possible for those pretty little candles to be the culprit.

Ghosting

Your friend in the industry,
Alan R. Mercurio

Oil Tech Talk

Jim Davis

Candles-Maybe Not!

Have inspected over a dozen structures with the "Black Soot Syndrome" as I call it. Because soot is commonly related to carbon monoxide I was called after HVAC contractors were blamed for faulty equipment. In 80% of the places I have inspected, no candles were in use. Having several samples tested by labs we have found mostly carbon (79%) and silicone (18%). The question that I had was why did 99% of these occurances appear in new construction or recently remodeled buildings only? It is a known fact that construction materials used today are full of chemicals such as glues, pressboard, drywall, paints, carpeting etc. I once read in a building magazine that all new construction needs to be baked and outgassed, which is rarely done. Staining of carpets around the baseboard is caused by infiltration, not exfiltration(Ghosting article).
I have received multiple calls from persons that recently had purchased pre-fab homes and they were black stained the day they moved in. Carbon Monoxide is eliminated fairly quick because to produce this kind of sooting, someones also has to be getting sick. To prove the point of building materials outgassing chemicals(VOC's)several homeowners agreed to allow Ozone generators to be installed in their HVAC systems. Within two days all new ghosting ceased. Within a few weeks the ghosting did not reappear after the ozone unit was turned off. No candles were used at anytime. Candles contribute to the problem but are by far not the main cause. But like anything else, it is easier to blame something you can see, rather than something you can't. Certainly blaming the occupants takes the blame off of everyone else.

BillW@honeywell

Also, the building may be under a negative pressure...

pulling in particulate matter from outside sources. This is fairly easy to diagnose, the carpets act like filters, and the soot is noticable at the doors and other points if entry. Again, here we have an issue with tight construction, restricted air changes, offgassing of platicizers and solvents; air has got to come from somewhere, and the house will be pulling it in from the path of least resistance.

jim sokolovic

Old house with candles...

Our house is about 40 years old, lots of drafts - original windows, doors, and oil boiler (but new burner). Light colored paint used in many of the rooms. My wife has been going nuts with burning candles, for a couple of years now - but we do not notice any markings, even though I can see the soot coming right off some of the coated decorative candles! I knew about the potential problem, and was expecting to have to repaint or clean the surfaces often from this. Thought this might help confirm the house tightness factor.

Mike T., Swampeast MO

Candles

I sell lots of candles in my store and likely burn 100s per year in there. Haven't noticed sooting problems.

A surprising number of customers don't really know how to burn candles--particularly heavily scented candles.

Wicks should be trimmed to ¼" BEFORE EACH AND EVERY LIGHTING! Longer wicks make a large, sooty flame and greatly magnify any problem with dripping--and I presume sooting problems on walls/ceilings.

Candles need to burn about ½ hour minimum (this is usually enough for heavily scented candles to take effect). After 1-3 hours of burning, extinguish and trim the wick to ¼".

Extinguish by pinching the flame with your fingers (or if you're afraid you'll be burned--you won't) a snuffer.

There is only one type of TRULY drip-free taper candle--they have hollow channels inside. Cut one and it looks just like "Honeycombs" breakfast cereal. Since there is less wax to begin with, they burn quite rapidly, aren't easy to find and are relatively expensive. Minimize dripping by ALWAYS keeping the wicks trimmed and using only homogenous candles. Those that are "overdipped" (they have a thin layer of color over translucent parafin) tend to drip much worse and burn unevenly.