I'm new here but wish I had found this site long ago. I have designed and built an in floor hydronic heating system for a new home I'm building in Ontario cottage country. Because we are located where natural gas is not available one of the aims of the new system is to take advantage of low rate electricity offered by the Smart Meter System soon to launched in Ontario. I am using a Monitron EH25 electric boiler to heat a 1000 gallon tank of water which will be my energy reservior. The boiler, through a closed circuit with a heat exchanger, heats the tank of water up to 180F at night when the power costs about 5.2c/ kWh. For a heat exchanger I'm using a modified automotive radiator situated in the bottom of the tank. This much is completed and works just fine. The heat loss calculation for the house indicates that the maximum heat loss to be around 60,000 BTU/hr. I have built most of the 2 manifold distribution system with 4 zones of
250 feet on each mainfold but am still trying to figure out how large a heat exchanger I will need for the heat distribution side of the system, this will also be a modified automotive radiator. Anyone have a calculation as to how many square inches of a copper water to water heat exchanger will be required to extract 60,000 BTU/hr and deliver an output temperature about 20 degrees cooler than the tank temperature?------------------------------------- Magicare