NATE Air Conditioning and Heat Pumps Practice Exam

What is the typical efficiency of a high-efficiency condensing gas furnace?

1. 70% to 78%

2. 80% to 90%

3. 90% to 98%

4. 99% and above

The correct answer is: 90% to 98%

A high-efficiency condensing gas furnace typically operates with an efficiency rating ranging from 90% to 98%. This level of efficiency means that the furnace is capable of converting a significant portion of the fuel it consumes into usable heat. The technology behind these furnaces includes a secondary heat exchanger that captures additional heat from the exhaust gases, which would otherwise be lost in traditional systems. By utilizing this remaining heat, high-efficiency condensing furnaces achieve better overall performance and energy savings, thereby reducing energy costs for consumers. While some options represent other categories of furnace efficiency, they fall short of the standards set by high-efficiency condensing models, which are specifically designed to achieve higher thermal efficiency ratings. This is crucial for both economic and environmental benefits, as burning less fuel translates to lower emissions and reduced impact on energy resources.