What does AFUE stand for in the context of heating efficiency?

AFUE stands for Annual Fuel Utilization Efficiency. This metric is used to express the efficiency of combustion heating appliances, such as furnaces and boilers. It indicates how effectively a heating system converts the energy in its fuel to heat over the course of a year. The AFUE percentage reflects the total heat output as a proportion of the total energy input, considering energy lost during operation.

For example, an AFUE rating of 90% means that 90% of the fuel consumed is converted into usable heat, while 10% is lost, typically through venting or other inefficiencies. This metric is particularly useful for comparing different heating systems and understanding their operational costs, as higher AFUE ratings correlate to more efficient equipment, resulting in lower energy bills for consumers. Understanding AFUE is crucial for both homeowners and professionals in the HVAC field as they make decisions about heating system installations and upgrades.