Lennox Residential
Email SignupSign up for email news

Need more information?

Our customer-care specialists are ready to answer any questions you may have.

Contact Us

Looking for literature?

You will find brochures for most Lennox® products in our archived documents section. If you need information on a model that isn’t listed, you can request literature by mail.


Frequently Asked Questions

Frequently Asked Questions

< back to list

Lennox Heating Systems

What are furnace ratings?

Furnaces are rated by the Annual Fuel Utilization Efficiency (AFUE) ratio, which is the percent of heat produced for every dollar of fuel consumed.

Like the miles-per-gallon rating on your automobile, the higher the AFUE rating, the lower your fuel costs. All furnaces manufactured today must meet at least 78% AFUE. If your furnace is 10 – 15 years old, it very well may fall below the current furnace minimum and waste energy.

This doesn't mean that you should only select a furnace based on its AFUE rating. The efficiency rating is just one factor to consider when looking for a new furnace.

Furnaces use electricity to run fans and motors. The amount of electricity used varies greatly depending on the type of furnace. Be sure to check electricity usage prior to making a purchase decision.

Popular FAQs in this Category


© 2014 Lennox International Inc.