Dry chemical fire extinguisher residue

[yooperkb]

This morning we had a small creosote fire in the stove pipe of our Vermont Castings wood stove and used our dry chemical fire extinguisher to put it out (we stuck the hose up the pipe and shot it up there).

We are definitely going to have it inspected even though we see no visible damage, but my concern is that the internet says that the chemical in the fire extinguisher (monoammonium phosphate) needs to be cleaned up with a baking soda paste. How would we clean inside of the stove pipe with that? It could take a few weeks for a chimney sweep to get to us, so I'm deeply concerned that the inside stove pipe is just corroding because of the chemical.

 

[EatenByLimestone]

Is it class A or a liner? Its easy to disassemble the class A and wash it out.

 

[yooperkb]

Is it class A or a liner? Its easy to disassemble the class A and wash it out.

It's double wall stove pipe, a ceiling support box, and then Class A chimney pipe in the attic all the way up to the roof.

 

[EatenByLimestone]

Pull it down and take it apart. Look it over closely for damage.

 

[brenndatomu]

Double wall stove pipe and class A chimney pipe are generally stainless steel inside, I'd not expect the powder to do anything much to it

 

[gthomas785]

Just sweep out the chimney till it's clean and inspect for damage from overheating.

 

[RockyMtnGriz]

Yeah, I wouldn't lose sleep over the agent eating your pipe. While it's probably best to clean it out, it's not going to just destroy things in a hurry. Flue gasses are a corrosive bunch on their own, so the pipe is designed to take it. Did you have a cat in this stove? I'd be most concerned about that.

Since you're probably going to replace the extinguisher you used, you might consider getting one of the bicarbonate based ones to replace it.

 

[bholler]

Double wall stove pipe and class A chimney pipe are generally stainless steel inside, I'd not expect the powder to do anything much to it

That's going to depend on the alloy. 430 I would be concerned 304 maybe 316 not so much