how does a central heating system work.?
A furnace or boiler in the lowest level, in the middle of the building, is used to make heat. Heated air, heated water, or steam are transferred from the heat source along ducts or pipes. A fan is used to push heated air thru ducts and thru vents in a room, to heat the room. Pipes are used to transfer hot water or steam to cast iron radiators in individual rooms. The radiators get hot and give off heat to heat a room. A water pump is used to move hot water. Steam pressure is used to move steam.
Well, it's pretty much like the name implies. There is a heating unit that is usually located near the physical center of the house and duct work running to each of the rooms. There is a large fan that draws in the air and pumps it into the heater. The heated air is forced out through the ducts into the individual rooms.
Cold air is passed through a heat exchanger and recirculated in an occupied space. Ther are a few types of central systems, boiler units, heat pumps, fuel fired furnaces, etc... With the exception of the terminal coil (radiator) boiler system, using a fan (or gravity with VERY OLD sytems) they pick up cold air in the return and send it through the unit to heat the air and send into the space as supply air. The configuration of the system has many possibilities with forced air but the gravity system which has no fan, must be centrally located with return vents on the ouside walls and supply vents on the inside walls.
