Can I Save Money With A New Furnace?
Replacing your old furnace is never cheap, but a new furnace could save you in the long run. Installing a new furnace isn’t always guaranteed to lower your heating costs as it depends in large part on how old your current unit is, its energy efficiency rating, and how well it works. Whether or not a new furnace will save you money and how much you could potentially save also depends on what type of unit you currently have and what type of replacement furnace you choose.
Understanding Furnace Efficiency Ratings
When considering replacing your furnace, you should always pay attention to Annual Fuel Utilization Efficiency (AFUE) ratings. AFUE ratings are the easiest way to tell whether a new furnace will save you money and also estimate how much you could save every month or year. The easiest way to understand AFUE is as a ratio or percentage of how much energy the furnace wastes and how much energy it converts into heat.
US Department of Energy regulations require all new furnaces to be at least 80 AFUE. An 80 AFUE furnace is 80% efficient, which means that it creates eight units of heat energy for every 10 units of gas it consumes. The other 20% of the energy the furnace uses is wasted as a result of some heat energy remaining in the combustion or exhaust fumes as they exit the furnace and are vented outside through the chimney or exhaust flue.
Furnaces that are rated between 80 and 89 AFUE are considered medium-efficiency units, while anything above 90 AFUE is a high-efficiency furnace. All high-efficiency units are condensing furnaces with both a primary and secondary heat exchanger. Medium-efficiency units only have one heat exchanger, which is why they can’t capture as much heat from the hot combustion fumes. The secondary heat exchanger in a condensing furnace works to capture the majority of the remaining heat energy from the fumes before they exit the unit so that the furnace more efficiently uses the energy it burns.
If your existing furnace is 80 AFUE, a 90 AFUE condensing furnace will reduce your heating costs by 10%. The highest-rated furnaces currently available are 98.5 AFUE, and this type of unit could easily save you several hundred dollars a year or several thousand dollars in just five years.
Single-Stage vs. Two-Stage Furnaces
If you’re looking to save even more on your heating costs, you may want to consider a two-stage furnace. Most furnaces are single-stage units, which means they always operate at full power. Two-stage furnaces have both high and medium power settings. This type of unit will typically run at the medium power setting around 80% of the time and will only ever switch over to full power on extremely cold days or if the furnace turns on when the temperature in your house is more than 5 to 7 degrees colder than the thermostat setting.
Two-stage furnaces have a three-way gas valve that can either be fully closed, fully open, or just partially open. When running on the medium power setting, the gas valve is partially open so that gas flows to the unit at only around 60-65% of the normal rate. This means that whenever a two-stage furnace is running on the lower power setting, it will use around 35-40% less energy than a single-stage furnace.
Whether a furnace is single-stage or two-stage, it doesn’t have any effect on its AFUE. This is because AFUE is solely determined by how efficient the unit is at capturing the heat it produces. You can find plenty of two-stage 80 AFUE units, and this type of unit will still only be 80% efficient no matter whether it’s running on the high or medium power setting. Nonetheless, a two-stage 80 AFUE furnace will still cost you much less to operate than a similarly rated single-stage unit.
Two-stage furnaces are more expensive than single-stage units, but the amount of money they can save you over time will almost always offset the higher initial cost. Two-stage furnaces also tend to last longer since they are under less strain and suffer less wear and tear whenever they run on the lower power setting. The decreased wear and tear can also help to lessen the potential repair needs. Another advantage of two-stage units is that they are far quieter whenever operating on the lower setting. Read here for more information on different types of furnaces!
Mike Bryant Heating & Cooling specializes in furnace installation and replacement services, and our technicians can assist you with choosing the best type and model of furnace for your home. We are a Lennox Premier Dealer, and we offer a wide range of high-quality furnaces that are sure to meet your home’s heating needs efficiently and effectively. For more information on our furnace installation services in Olathe and the Kansas City area, contact us today.