What is the typical AFUE rating range for a natural gas induced draft heater?

The typical Annual Fuel Utilization Efficiency (AFUE) rating range for a natural gas induced draft heater is around 75-84%. This rating is an important measure of a heating system’s efficiency, indicating the percentage of fuel that is converted into usable heat for the home versus what is lost in the combustion process.

Induced draft heaters utilize a fan to draw combustion gases through the heat exchanger and out of the home, allowing them to operate at higher efficiencies than natural draft systems, which rely on natural airflow. While variations in AFUE ratings do exist across different models and manufacturers, the range of 75-84% represents a common efficiency level for mid-efficiency units in the market.

Higher efficiency systems, such as those rated between 85-95% or even 95-100%, are categorized differently, typically offering advanced combustion technologies or condensing methods that maximize heat extraction. However, these systems are not classified as standard induced draft heaters, leading to the distinction in rating ranges.