What is a gas furnace’s role in a home’s HVAC system?

A gas furnace plays a crucial role in a home's HVAC system primarily by providing heating. It is designed to burn natural gas or propane to generate heat, which is then distributed throughout the house via ductwork. This process ensures that the living space remains comfortable during colder seasons by raising the air temperature.

While filtering indoor air is an important function of the HVAC system as a whole, it is specifically the air filters within the system and not the furnace itself that perform this task. Ventilation involves bringing fresh air into the home and removing stale air, which is often achieved through separate mechanisms or components like exhaust fans or air handling units. Cooling a home is typically the responsibility of an air conditioning unit or heat pump, rather than a gas furnace, which is specifically designed for heating purposes. Therefore, the primary and essential function of a gas furnace in the HVAC system is to provide efficient and reliable heating.