The answer to 'what does furnace do' is a furnace is a central heating system that warms your home by burning fuel, such as natural gas, propane, or fuel oil, to create heat. The furnace takes in cool air from your home, heats it, and then circulates the warm air back through your ductwork and vents to distribute the heat throughout your living spaces. Furnaces are an essential component of a home's HVAC (heating, ventilation, and air conditioning) system, providing reliable and efficient heating during the colder months.
Furnaces come in a variety of sizes, fuel types, and efficiency ratings to match the heating needs of your home. They are typically located in the basement, attic, or a dedicated utility closet, and they work in conjunction with your home's ductwork to deliver warm air to the rooms in your house. Regular maintenance and professional servicing are important to ensure your furnace operates safely and efficiently.