Burning creosote? (flu & chimney)

[shanxk8]

Something strange happened during the last firing to cook pizza on the weekend. Near the end of cooking when there was only coals on one side of the oven, I was going to put the last pizza in the oven and noticed some burning flecks inside the flu area. As I was taking pictures the burning flecks were radiating out and up into the chimney. (See pictures, should have taken video )

I figure this must be creosote buildup in the flu and chimney that is burning. I was a little surprised as I've only been firing the oven since early July (~3 months).

Is this something other people have seen in their ovens?
Does this mean I need to clean for creosote? How frequently? What is a good method?

[shanxk8]

Has nobody else experienced anything like this with their oven? Or is it so common that its too obvious a question to ask?

I genuinely would like to know if anyone else does chimney & flu cleaning, and how they achieve.

[mk e]

I was told by my oven builder brother to be sure to make my chimney cap removable so it's easy to clean every couple years....so you're not alone.

[JRPizza]

I've seen it with my oven, especially if I hold some burning newspaper (or lately my propane wood burner ) under the flue to get a hot draft going. I only have a thin layer of deposit so am not going to worry about it until it starts to build up some more. The duravent cap I used is supposed to be removable, so when the time comes I'll find out how locked on it really is. If someone has suggestions on how to know when it is time to do a sweep I'd like to hear it too

[shanxk8]

So, I had a nice rolling fire the other day. Flame was so nice that it was kicking up outta the oven into the chimney.

That outta clear out some of that creosote