When heating our homes during the winter months, there’s a balancing act many of us struggle with: keeping our family warm vs. saving money where possible.

If you’ve found yourself shaking your head at gas and hydro bills, wondering how you could make things better, you’re not alone.

Many people find themselves burdened with high heating costs as a result of their outdated furnace. A high efficiency furnace could be saving you hundreds of dollars on energy bills each year. Let’s find out how.

Older Homes in Ottawa Tend to Have Less Efficient Furnaces

Furnaces are vital component for winter living in Ottawa and Eastern Ontario.

If you’ve ever found yourself with no heat thanks to a furnace that’s broken down (or even due to a power outage), you know that a house can get pretty cold pretty quickly with no heat source.

old used furnace thrown awayHomes built in the 1980s, 1990s and even into the 2000s had furnaces that were solid, dependable, and heated the house just fine.

But they came with a price.

Those furnaces were not highly efficient. They often were made to a standard rating of around 78% AFUE (Annual Fuel Utilization Efficiency).

Today’s high efficiency furnaces, meanwhile, must have a rating of 90% or more. Many high efficiency furnaces available in Ottawa now reach

What does that translate to, in terms of gas bills or hydro bills?

Well, that older, less efficient furnace could be costing you hundreds of dollars each year in heating costs.

How the AFUE Rating Works for Furnaces

AFUE is a commonly accepted standard rating of furnaces in Canada.

AFUE essentially tells us how much heat is produced by the furnace for every dollar of fuel consumed.

house in winterThis furnace rating also tells us how much energy (regardless of whether the furnace’s energy source is gas or electric) is being wasted as a result of inefficient burners, air leaks and/or inferior design.

Let’s take an example of a furnace that you might see for sale today:

AFUE: 90%


90% of its energy source (gas or electric) turned into heat


10% of the energy being wasted

As you can imagine, a high efficiency furnace needs the lowest AFUE possible for its class. And as we go forward, the AFUE rating standard is getting higher.

How High Efficiency Furnaces Perform Better

family plays in warm houseFurnaces contain several key components of operation:

  • Combustion chamber
  • Heat exchanger
  • Burners
  • Blower
  • Flue

Let’s focus on the combustion chamber and heat exchanger, as these are where high efficiency furnaces distinguish themselves.

The combustion chamber is where fuel and fumes are burned to create heat.

High efficiency furnaces have a second combustion chamber, collecting fume runoff (e.g. gas fumes) that would otherwise have escaped, condensing these into a liquid and burning these again to generate additional heat.

That means that they are using less of the original fuel source (gas or electricity) in the long run as opposed to traditional, older furnaces.

High efficiency furnaces also add another set of heat exchanger coils or tubes. These metal tubes or coils are heated up as the burners combine fuel and air to create heat. Since they stay hot as long as the furnace is in operation, a second set of coils or tubes means more heat is generated.

Both these additional features are what make high efficiency furnaces just that: More efficient to run, requiring less energy, translating to lower heating costs.

A Furnace Investment That Pays Good Returns

You could save $300-$400 a year by investing in a high efficiency furnace today.

This is based on switching from a furnace with 78% AFUE to one with 90%. You could save even more as the AFUE number goes up. The comparison tilts further if you have an older furnace, say 25-30 years old.

Furnaces, like practically every other product on the market, are designed and built with an intended lifespan in mind.

If you’re nearing the end of your furnace’s forecast lifespan, moving up to a high efficiency is a no-brainer.

But what if you have a furnace that’s still got some years on it? Should you buy a high-efficiency furnace then?

It’s best to run the AFUE numbers, as well as the cost of the fuel source, to see what works best for you. There will be individually varying factors to consider, such as how large of a home you are heating and what temperature you are comfortable with heating it to.

To find out more about how a high efficiency furnace could be right for you, contact Advanced HVAC today.

We’ve sold, installed and serviced thousands of high efficiency furnaces in Ottawa and surrounding communities.