"I thought anybody with any experience could guess around how much heat could be generated from a cast iron box of a given size and weight and how it compares to the heat required by a 2 1/2 car garage"
That's where you went wrong; pros (experienced people) don't guess, they use manufacturer data. They especially won't guess from such insufficient data. Now is the time to get sophisticated in thinking enough to realize the meaning of insulation and size instead of living in an impossible dream; that will make you thankful.
www.heatpro.us energy businessmen's knowledge
Yes, you really have to find out the MAKE and MODEL to get good answers. There IS more than one machine made.
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