Soot on ceiling areas around heat outlet registers

[Rebel1]

The standard explanation is dirt (or soot from candles) in the rooms accumulates around the registers due to airflow as show in the diagram here about 1/3 of the way down, where it says "Dirt on the ceiling":

The gal who lives in the apartment keeps it quite clean. She regularly burns candles (mostly the expensive Yankee brand) and has been doing so for over nine years. The soot problem just started about four days ago. She hasn't switched brands or even started burning new candles from the same company. Also, while the soot is most visible against the white ceilings within six or so inches from the registers, cups just sitting on counters about 30" above the floor are also coated with soot/dirt.

She keeps the wicks trimmed. I guess it's possible that the bottom of a wick has a defect that only shows up as the upper portion of the candle burns away, but there hasn't been visible smoke.

Last Saturday, the smoke alarm went off in her apartment. Couldn't tie it directly to the candles, but after she put them (four or so) out, the alarm stopped.

The problem is most intense in the kitchen, which also happens to be the closest room to the gas furnace located in the attic above her kitchen. The more distant the register, the less noticeable the soot. (Also, no candle burning in the distant room.)

The furnace is about nine years old, so a leak in the air exchanger is unlikely. Even if there is one, there also would have to be incomplete combustion of the gas to allow carbon particles to mix in the heated air to her apartment.

Thanks for your ideas.

R1

[TomR]

Is it oil heat, gas heat, or ....?

I would be concerned about a cracked heat exchanger and, of course, you need to make sure you have CO detectors in the apartment.

In one property that I own, which has oil-fired hot air heat, similar issues were noticed, including the smoke detector going off. I had an HVAC person come out right away and all it turned out to be was a build up of soot in the connector pipe that goes to the chimney. He cleaned out the pipe and cleaned and serviced the whole heating unit and the problem was solved. No cracked heat exchanger.

[jamesgangnc]

Black mold. I get it near the duct outlets on some vents. Cleans off with a damp cloth and a little cleaner.

[Rebel1]

As the two paragraphs say, it's gas.

[Rebel1]

That might be, which could explain why my nose gets stuffy when I visit her even though I don't have a confirmed mold sensitivity. However, the soot also coats cups on counter about 30 inches above the floor.

[RonB]

I would put mold second on my list and investigate the possibility of it being Carbon Monoxide as two previous posters has stated.

AND I WOULD DO IT NOW!!!!!

Call the local fire department and see if they will bring instrumentation out to check this. Again - NOW. Before you have a fatality.

[TomR]

Opps, sorry. I guess I should have had my reading glasses on and/or put my brain in gear when I was reading what you originally wrote.

[Norminn]

Damn right! Let us know. And good luck.

[Stormin Mormon]

Monoxide is a clear, colorless gas, about the same dentisty as air. Wouldn't lead to soot.

nose, not on the list.

Christopher A. Young Learn more about Jesus

.

I would put mold second on my list and investigate the possibility of it being Carbon Monoxide as two previous posters has stated.

AND I WOULD DO IT NOW!!!!!

Call the local fire department and see if they will bring instrumentation out to check this. Again - NOW. Before you have a fatality.

[Stormin Mormon]

stuffy nose on the list of symptoms?

The soot may be coming from a cracked heat exchanger.

Christopher A. Young Learn more about Jesus

.

Damn right! Let us know. And good luck.

[Rebel1]

In response to various suggestions, I had her hold a carbon monoxide detector a few feet below the register closest to the gas furnace for a few minutes while the heat was on. No alarms.

The building has two levels and two furnaces, one for each level. Each level has two apartments. My next step will be to have her ask the other tenants if they are having a similar soot problem.

I post the results.

R1

[Robert Macy]

If the origin is NOT new formulation of candles and NOT cracked heat exchanger/build up and IS black mold; you can try a test. Place open vinegar or bleach, or paper towels soaked in vinegar or bleach, near the intake and see if the balck streaking stops - and if your nose stops feeling stuffy when you go in there. The vinegar will make the house smell like salad dressing, and the bleach will make it smell clean, so it's a win-win, ...a bit anyway.

[Rebel1]

Excellent suggestion. I'll try that in a couple of days when I next go there.

Thanks,

R1