A furnace blows heated air through the house through air registers or grills. This distribution sytem can be powered by Natural Gas, Electricity, or Oil.

Boiler systems distribute heat in hot water, this heat passes through radiators or other devices in the rooms throughout the house. residential boilers generally use natural gas or heating oil.

Heat pumps work as two-way air conditioners, during summer an air conditioner works by moving heat from indoors to outside. In the winter the heat pump reverses this by using the cold air and heating it up and moving that heat inside the house.

Water heating is a heat process that uses an energy source to heat water above its initial temperature, this is used for domestic uses of hot water such as cooking, cleaning, bathing, or space heating.