Most furnaces these days are purchased with two factors in mind:

  1. Price.
  2. Efficiency.

Modern furnace models are always more efficient than those made 20 or more years ago, and there are a range of performance options across budget levels. Budget is primarily impacted by efficiency, and the efficiency rating of a new furnace is expressed through Annual Fuel Utilization ratings (AFUE).

Here’s how you can decipher AFUE and find the best balance between efficiency and price.

How AFUE ratings work

The AFUE rating applies to all furnaces using:

  • Propane
  • Natural gas

The rating is read as a percentage of fuel paid for vs fuel returned as heat. So a furnace with a 98% AFUE rating returns 98% of the fuel you pay for as heat. The remaining 2% is lost in the conversion and burning process.

Once a new furnace is manufactured, it is evaluated based on the energy losses that occur due to changing demands, and during the cyclic on and off functions.

This calculation is made based on ideal circumstances, including error-free installation. It’s worth noting that not all furnaces are the same, and specialized installation knowledge for each manufacturer is required for error-free installations.

Minimum requirements for new furnaces

Canada is a leader in furnace energy efficiency requirements.

The Canadian federal government requires a minimum AFUE of 90% on new furnaces.

How much $$$ can you save?

Switching to a newer and more efficient furnace will lead to cost savings, but most homeowners don’t know exactly what to expect. Will a new furnace allow you to save for a trip down south? Or skiing in the alps?

The American Council for Energy Efficient Economy broke down the savings that could be experienced when a homeowners switches from an old furnace of 50% AFUE, to a new model with a 95% rating.

  • For each $100 a homeowner with the 50% model spent, a homeowner with a 95% AFUE furnace would spend $53. Potentially thousands of $$$ in savings in a year.

For the sake of simplicity, it works out to about $1 per percentage of efficiency. So a 98% AFUE furnace will save about $40 per month on a $200 heating bill over an 80% AFUE furnace. Over the lifetime of the furnace it will pay for itself, a replacement, and a trip for the whole family down south. Not bad!

Sign up to receive helpful home comfort tips and reminders
  • This field is for validation purposes and should be left unchanged.
  • climate-care
  • energystar
  • hrai
  • TSSA
  • wsib
  • Waterloo-Region-1
  • Waterloo Region 2023