copper or cast iron?

Jesse_2

I need to replace my 175K btu gas boiler for a 2 unit bulding about 1200 sq ft each unit that I might sell in a year but I want to have an effecient winter. I am getting different estimates. one says go with a 160k btu COPPER boiler at $2,850 the other says to go with a 175k btu WILLIAMSON CAST IRON boiler at $4,000 including replacing a busted radiator that I have in one of the units. Can anyone give me any advise on this to make a wise decision?

Brad White_130

Cast Iron

Cast Iron would be my choice. But size it to a real, calculated heat loss. You can use copper but be sure to use P/S piping with a dedicated circulator for the boiler. But all things being equal, cast iron will outlast a copper boiler at least twice. Copper has it's place (fast response, low water content and mass), but every one I have seen would benefit from some mass. Not the last word, just my personal experience.