The furnace can be located up to 500 feet away from the home or buildings being heated. Heated water from the furnace is pumped to the home or building through insulated, underground pipes -- the most efficient way to move heat over distances. Central Boiler Furnaces are designed to work with any existing heating system. A heat exchanger or direct circulation conveys the heat into a forced-air furnace, boiler, or radiant floor heating system. This gives you normal thermostatic temperature control.