It's noisy: Forced-air heating can be noisier than other types of heating systems. Ducts carry allergens and dust: If not cleaned and regularly maintained, dust and other allergens can collect in the ductwork and forced-air unit. The blower can push built-up contaminants into the home when the heat turns on.

Forced-air furnaces are extremely efficient. Furnaces have a high AFUE rating around 78-84%. AFUE rating stands for “Annual Fuel Utilization Efficiency.” The higher the AFUE percentage the more heat the furnace can deliver relative to the amount of fuel consumed.

How Does Warm Air Heating Work? Warm air heating systems typically work by drawing in cool air from the outside using a vent and warming it up by passing it over a gas flame or to a heat exchanger. The warm air is then circulated throughout the entire house through air ducts, vents or grills in each room.

Forced air heating relies on a furnace or heat pump to distribute warm air through a network of ducts, while central heating uses a central heating unit, such as a boiler, to circulate heated water or air through pipes or ducts to radiators, baseboard heaters, or underfloor heating systems.