Serving the entire Portland Oregon Metro Area
Midway Heating Company
Aug 28, 2017

Things you should know when doing a furnace comparison

Portland Furnace InstallationYou’ve decided to replace your aging furnace with a more energy efficient model.

Here’s some information so you can do a furnace comparison and understand the features available.

What’s AFUE?

Let’s start with something basic-the AFUE rating.  Every new furnace has an AFUE rating and it stands for Annual Fuel Utilization Efficiency.   I know that sounds really complicated, but it’s not.

The AFUE number tells you now efficient a furnace is at converting fuel to energy so the higher the percentage, the more energy efficient the furnace.

For example, a 98% AFUE-rated furnace means that 98 cents out of every dollar you spend goes towards heating your home.

Single-stage vs. 2-stage furnace

A single-stage furnace runs at full capacity every time it turns on as it only has 1 stage or setting (that’s where the name comes from).  A two-stage furnace has 2 stages:  low and high.  The low stage runs the majority of the time and the high stage kicks in when extra power is needed to heat your home to the desired temperature.

As you might have already guessed, a 2-stage furnace is more efficient than a 1-stage furnace as it doesn’t need to run at full speed every time it turns on and using less energy when it’s running on the low stage (which is usually around 75% of the time).

Variable is good when it refers to a furnace

A variable speed motor actually refers to the furnace’s indoor blower motor, which moves at different speeds to control the flow of the heated air throughout your home.  This results in a quiet and consistent flow of air for the perfect balance of temperature and humidity in your home.

A variable-capacity operation works like the cruise control on your car as it automatically makes adjustments so you get the maximum fuel efficiency from your furnace.

2-stage or variable speed furnaces are some of the most efficient furnaces available.  They also provide great comfort as the 2-stage and variable speed blower work together so there’s no big temperature swings.

98% AFUE-rated furnace from LennoxEnergy Efficient furnace comparison

A great example of an energy efficient furnace is the SLP98V from Lennox.  It’s a 98% AFUE-rated furnace that has earned the ENERGY STAR Most Efficient 2012 label (having the ENERGY STAR label means the products have met strict energy efficiency guidelines set by the EPA and U.S. Dept. of Energy).

Precise Comfort™ technology, using icomfort or a traditional 2-stage thermostat, allows the SLP98V to adjust its output to respond to different conditions without wasting energy.

By constantly monitoring and automatically adjusting heat and airflow, it can change its output from 35% to 100% in increments as small as 1% to provide an even temperature and consistent comfort.

By comparison, a 1-stage furnace operates at full heating capacity every time it turns on so you can see how the SLP98V would be more efficient.

Another Lennox innovation in the SLP98V is AirFlex™ technology, which allows the technician to adjust every aspect of the airflow to best match your lifestyle, home layout and geographic location.

The furnace blower moves conditioned air through the duct work in your home and AirFlex™ technology controls the amount of air delivered by your system.

Now you’re ready to talk to a professional

The installation of a gas furnace needs to be done by professionals and once they talk with you about your budget and comfort requirements, they’ll take a look at your home and be able to recommend several furnaces which would work for your situation.

Even though they will narrow down the choices for you, it’s good to know the basics as it will help you understand what you are buying and how much money you can save on your monthly energy bill.

Final thought

A new gas furnace is an important decision and one you want to take seriously as you’re going to have to live with that furnace for many years to come.  For other ways to make your home more efficient, visit the It Pays To Live Smart website.