59 deg is pretty chilly inside, however given the fact that it was -26 outside without the wind I'd say your stoker was doing a decent job. It got down to -10 where I'm at a couple of times and I had a rough time keeping it at 66. My house is pretty drafty but I'm still pleased with it. I did have to supplement with the propane stove for about a half hour during the reloading process...shh don't tell anyone haha. I love winter however this minus crap is getting old.