I have an Ashley side-door wood heater in my basement. I like it for the most part, but sometimes if the conditions are right, the thimble into the chimney will get extremely corroded with creosote. I'm not talking about the brittle, foamy stuff that brushes out easily. This stuff is like black hot-melt glue. When it's cool, you can chip it with a screw-driver. If it gets in the pipe, you can take the pipe outside and burn it out (and it certainly does burn).
However, I have some that has run down my brick work. I have chiseled off a lot of the solid part, but it has left a bad stain.
Any idea what might disolve this stuff? It will be indoors, so I have to be careful about fumes and such. I thought about oven cleaner, but I thought I'd ask first. Figured somebody here would have a trick up their sleeve.
Thanks,
Don