I cleaned mine (and my grandfather’s) every year.
Mine wasn’t a big deal, but my grandfather’s definitely needed it. He always seasoned his hardwood at least two years, but it was an old farmhouse. The ‘attic’ (my bedroom when I was there) was poorly insulated and COLD. He generally got some buildup.

The beauty of having the exterior boiler is that I don’t have to deal with that schit.

Last edited by NH K9; 11/29/19.
�Out of every one hundred men, ten shouldn't even be there, eighty are just targets, nine are the real fighters, and we are lucky to have them, for they make the battle. Ah, but the one, one is a warrior, and he will bring the others back.�