Burner Flame Mystery

ccstelmo

Try this.
On any fossil fuel flame, whether on a water heater, or a boiler or a furnace, remove the sheet metal so the flame is open to the room, lean close to the opening, and clap your hands in front of the flame.

You will see the flame turn orange for a moment then re-establish itself blue.

What's with that?

ccstelmo

mattmia2

sodium

ScottSecor

Dust

MikeGordon

Momentary disruption of the primary air mixing with the fuel, prior to combustion.

The clap creates a short, relatively high pressure air zone where the primary air is drawn into the burner, near the gas orifice. This creates a disruption of the air, and a richer fuel/air mixture, for a brief period. When the richer mixture reaches the flame front at the burner face, it burns orange for a brief period.


Mike Gordon

Larry Weingarten

Hmmm, This is an interesting question. I was imagining that a clap would produce a small shock wave, knocking dust or whatever loose, so it was put into the air supply to the burner. Then you see it as a change in flame color... So a test comes to mind. If the amount of change in the flame decreases with repeated clapping, my dust theory could apply. If it remains constant, it must have to do with the fuel.

The real question is what the homeowner will think about you applauding their fuel burning appliance

Yours, Larry

EBEBRATT-Ed

Dust

EdTheHeaterMan

It's Magic.

ScottSecor

I am not suggesting you are not increasing air for combustion (temporarily) when you clap your hands.

I can tell you for a certainty that if you sweep the floor with a dust broom near an atmospheric burner you will notice an orange flames. I've also noticed that something similar happens with power burners as well when you kick up dust near the combustion air inlet.

Jamie Hall

Yeah. Dust. Sodium is a component of almost all dust -- and it takes very very little to produce that intense orange flame. Changes in combustion air may make the flame yellow, but that is a very different colour (and it is well to learn the difference...).

dullknife1

Best laugh I had in a while Ed 

ccstelmo

I too am inclined to agree with Ed.
But for the sake of eliminating the dust theory, I'll vacuum around my boiler and into and around the (atmospheric) air door. Then I'll wash the floor and applaud the flame again.
This won't happen soon because I'm gone again stamping out brush fires that keep cropping up in my life but I'll get back to you.
ccstelmo

dko

You know when there's a window with a light beam shining through and you can actually see every speck of dust flying around? That's all around the boiler as well. Unless you set up your boiler room like a car paint spray booth and walk in naked it's probably not worth the experiment.

ethicalpaul

Just how dusty and salty are all y'alls hands anyway?

Jamie Hall

It takes astonishingly little sodium to get the orange. Milligrams or less in a typical flame.

EdTheHeaterMan

I still say "It's Magic".
No matter how much salt I rub on my hands before illustrating this magnificent feat of prestidigitation.

Tim McElwain

It is MAGIC created by the DUST fairy. That same fairy leaves his calling card all over the place on tables and furniture just to keep us busy DUSTING!

Big Ed_4

The burner is designed to fire contained , to intense the burning ..

mattmia2

How much stuff is knocked loose from your hands when you clap them? There is plenty of sodium in your dead skin and the bacteria and all the other stuff that is on you skin.

mattmia2

It happens on a gas cooktop when you jostle a pan over the grates too.