BEAT THE HEAT! Click here to book your AC or Heat Pump quote today.

Understanding Furnace Efficiency

Your heating bills are a reflection of the weather, furnace efficiency and how well your home resists temperature change. While you can’t do much about the weather, you can make a difference in furnace performance and home energy efficiency.

Furnace Ratings

Combustion furnaces and boilers have AFUE (annual fuel utilization efficiency) ratings that tell you how effectively they use the fuel they consume. Even though the furnace may use a therm of gas, it doesn’t produce the same equivalency in heat for the home. The AFUE measures the amount of heat that the gases produce that goes up the chimney as exhaust gases.

A heating system that wastes 20 percent of the heat up the vent pipe has an AFUE of 80. One that wastes only 10 percent has an AFUE of 90. Higher AFUE ratings in this climate translate to lower heating costs, since less fuel is wasted.

The most energy efficient furnaces and boilers have AFUE ratings close to 100, which means that they waste little fuel as combustion gases. These systems are called condensing furnaces and boilers and work by extracting more heat from the combustion gases. They use a second heat exchanger so that the only combustion waste they produce is condensed water.

Besides the Furnace

While furnace efficiency is measured by its AFUE, other aspects of your home influence your heating costs. How well your home is insulated, the number of air leaks, and quality of the windows can raise or lower heating efficiency. How tightly the ducts are sealed matters, as does how well you keep your system maintained.

An annual tuneup improves efficiency because all the parts are cleaned and adjusted. Changing the air filter routinely makes a big difference, as well, since the airflow through the blower won’t be hindered by dust on the filter.

Besides opting for higher furnace efficiency when replacing your existing equipment, taking care of your existing equipment and improving your home’s energy efficiency will result in lower heating bills. For more information, contact Arpi’s Industries, providing HVAC services for Calgary-area homeowners.

Our goal is to help educate our customers in Calgary, Alberta about energy and home comfort issues (specific to HVAC systems). For more information about other HVAC topics, download our free Home Comfort Guide.