...the burning kind..... I have an enerzone 2.5 zc that does the best it can on our house (3000 sq feet including the finished basement) but it could definitely use some help. Of course the regular furnace helps now but I've got the Blaze King fever. So up pops a used princess insert on CL that could easily fit into my gas insert location (a real nice Mendota unit). 2000 bucks with the liner and one year of use. Good deal?