Hot Water Versus Steam Heating. In a household hot water heating system, water is delivered to the radiators at 70.0oC(158.0oF) and leaves at 28.0oC (82.4oF) .The system is to be replaced by a steam system in which steam at atrI1aipheric pres· sure condenses in the radiators and the condensed steam leaves the radiators at 35.0oC (95.0oF). How many kilograms of steam will supply the same heat as was supplied by 1.00 kg of hot water in the first system?