Hello,
I am looking to convert from oil to gas and we have had multiple plumbing companies come and give us estimates on gas boilers. We have had a pretty significant difference in the size of the conventional boilers that we were quoted for. One recommended a boiler that was a 132,500 standard BTUs (Buderus) while another recommended a 105,000 standard BTUs (Burnham).
Our home is 1470 square feet (however, that is not including the basement, which is heated and another 700 sq ft) and has 3 zones. We want to make sure that we are not getting a boiler that is oversized, lowering its efficiency.