The voluntary EnerGuide label
Energy efficiency in furnaces is measured by the annual fuel utilization efficiency (AFUE) rating. This is a seasonal measure of fuel efficiency only. It does not include the electrical energy required to operate controls, fans or pumps.
The higher the AFUE rating, the more efficient the unit is.
A furnace’s voluntary EnerGuide label displays the model type and AFUE rating. It also uses a pointer to show where that rating falls on a scale of energy efficiency for similar models. Use the AFUE rating value and EnerGuide scale to compare furnaces.
The EnerGuide label may appear beside the ENERGY STAR® symbol for certified models.
EnerGuide label for a gas or a propane furnace

EnerGuide label for a gas or a propane furnace
The black and white EnerGuide label indicates the annual fuel consumption of a gas or propane forced-air furnace as a percentage. The manufacturer indicates what the percent number is for each model. The efficiency ranges from 90 percent to 98 percent.
EnerGuide label for a gas or a propane furnace with a high efficiency motor

EnerGuide label for a gas or a propane furnace with a high efficiency motor
The black and white EnerGuide label indicates the annual fuel consumption of a gas or propane forced-air furnace as a percentage. The manufacturer indicates what the percent number is for each model. The efficiency ranges from 90 percent to 98 percent.

EnerGuide label for an oil furnace

EnerGuide label for an oil furnace
The black and white EnerGuide label indicates the annual fuel consumption of an oil-fired forced-air furnace as a percentage. The manufacturer indicates what the percent number is for each model. The efficiency ranges from 78 percent to 96 percent.
EnerGuide label for an oil furnace with a high efficiency motor

EnerGuide label for an oil furnace with a high efficiency motor
The black and white EnerGuide label indicates the annual fuel consumption of an oil-fired forced-air furnace as a percentage. The manufacturer indicates what the percent number is for each model. The efficiency ranges from 78 percent to 96 percent.

The ENERGY STAR name and symbol are trademarks registered in Canada by the United States Environmental Protection Agency and are administered and promoted by Natural Resources Canada.