I have been kicking around the idea of putting in a Englander 13 PNC in my basement. It is 672 sq ft , three of the walls are insulated and the forth is 80 % below ground level. I bought one of those electric oil filled radiator heaters and it brought the temp up 6 degrees in 16 hours[ FROM 42-48 F ] . I had a vent less 10000 BTU gas heater in last year before I insulated the walls and it brought the temp from 38- 50 in about 24 hours. That being said I think I need about 15000 to 18000 BTU to heat that area. I was hoping to heat the first floor [ SAME SQ FT] along with the basement. Will the Englander do the job ? Or am I just throwing away money trying to accomplish this . Still have to find a chimney guy also .