On Mon, 11 Jan 2016 22:09:05 -0800 (PST), Uncle Monster
wrote:

On Monday, January 11, 2016 at 10:33:00 PM UTC-6, wrote:
On Mon, 11 Jan 2016 20:16:57 -0800 (PST), Uncle Monster
wrote:

On Monday, January 11, 2016 at 9:33:25 PM UTC-6, wrote:
On Mon, 11 Jan 2016 14:01:13 -0800 (PST), wrote:

Important basic info

Rollout means the fire has "rolled out" from where it
belongs and a part of the heat exchanger that is not
supposed to get hot, is getting too hot.

So obviously this could be dangerous.

If you reset the swicth, I would watch the
the burner operation carefully for a while
to make sure the fire stays here it belongs.
That can be difficult if there are lockout safteys on the
cabinet.

Mark

Overfueling due to gas pressure set too high will cause roll-out -
particularly on light-off. If you hear a big "whoomph" on startupget
the pressure checked.

The gas control valve will lock out if it's supplied with more than around 13 inches water column. The pressures will be listed on the label. There is an internal adjustable regulator for setting the output pressure to the burner manifold which is usually 3.5 inches water column. In The U.S. the normal gas pressure supplied by the regulator at the gas meter to natural gas appliances is approximately 8 inches water column. (*?*)

[8~{} Uncle Pressured Monster
It is the adjustment of that "internal regulator" I'm talking about.
Changing from 3.5 to 4.2 inches can cause flame roll-out and also
cause high CO emissions. Some "quacks" will adjust the pressure up
trying to get more heat out of a furnace. It needs to be set properly.

Oh yea, you mean the idiots who think a yellow flame puts out more heat? O_o

[8~{} Uncle Flaming Monster
You can have an overfueled burner in today's tube burners with no (or
extremely little) yellow in the flame, and still get roll-out (and a
noisy flame)