A furnace is part of an HVAC system that is used to generate heat for your home. A furnace is a heating unit, while HVAC is the system that includes heating and cooling units, ducts, and vents to distribute the conditioned air in a building.

This system is responsible for heating and cooling your home and includes products like furnaces, air conditioners, heat pumps as well as ductwork, thermostats and other home comfort controls.

To cool air, the fan in an air conditioning unit from Frigidaire, Coleman, and other HVAC companies draws the air in and forces it over the evaporator's coils. Filled with refrigerant, these coils draw heat from the air, cooling it. Next, the air moves into the air handler, where a blower sends it into the ducts.

Most traditional central heat and air conditioners use electricity to cool and heat your home, but some systems, known as gas-powered or propane air conditioning systems, utilize natural gas or propane as part of the heating process in a split system.