The three common central heating systems are furnaces, boilers, and heat pumps.
Furnaces are the most common form of central heating system. A furnace is an appliance that heats up air and blows it through the ducts via air registers or grills. A furnace can be powered by electricity, natural gas, or fuel oil.
Boilers heat up the same way that furnaces do. But instead of heating air, boilers heat water. The hot water is then distributed through a radiator or another device.
A heat pump is simply an air conditioning unit operating in reverse. In the summer, heat pumps or AC units cool off s by removing the hot air and pushing it outside. In the winter, they heat by removing the cold air and pushing it outside. The two most common heat pumps are ground-source heat pumps that use the heat from the ground, and air-source heat pumps that use the heat from the outside air.
All three central heating systems come with a list of pros and cons.