I have an old square one like that in my basement.....we have never used it,,,,,hubby is not allowed to mess with fire inside.....he set the roof on fire at the old house....
They can be dangerous... chimney is cleaned twice a year, and flu pipe also cleaned when chimney is done. We have two more of them we don't use yet, one larger, one smaller... hope to have the right place to use them when we eventually move out of here and find property.
I have a perfect place for 2 of them. The new house has a chimney between the kitchen & garage & used to have 1 on each side. Everything is still there but the stove & connector pipes.