Everyone wants to find ways to reduce their monthly home heating bills. One way to do that is to install the most cost-efficient furnace that is on the market.
When you start searching for high-efficiency furnaces, you will notice a big difference in price when it comes to units with the best efficiency. But you need to know whether all of that extra cost is worth it.
Let’s explore whether a high-efficiency gas furnace makes sense for your home.
What does high-efficiency mean?
The efficiency of a furnace helps determine how much savings on monthly heating bills you might expect. If you have shopped for furnaces, you likely have seen references to percentages like 80% and 95%. This references the furnace’s Annual Fuel Utilization Efficiency, or AFUE. A furnace’s efficiency is measured by the AFUE rating, which is basically like gas mileage for your furnace. The higher the AFUE rating is for a furnace, the more efficient the unit is.
For example, a furnace with an AFUE rating of 95% does not need as much natural gas fuel to heat a home as a furnace rated at 80% AFUE would need. Now, the 95% AFUE rated furnace will cost more upfront to purchase. But the unit will save the property owner monthly heating costs for years to come.
The reliance on more energy efficient units is particularly important for property owners who live in colder climates. The price difference for warmer climates may not be as dramatic as for colder areas, meaning the higher efficiency furnace isn’t expected to produce as much savings in monthly bills. In that case, it may not be worth paying so much more up front to purchase a highly efficient furnace to heat homes in warmer climates that may not experience as much cold weather.
How furnace technology impacts efficiency
Now that you understand how a furnace’s efficiency is measured, it is helpful to know how furnace technology affects operation, purchase price and operating expenses.
There are different types of furnaces to consider when shopping: single-stage, two-stage and variable-speed furnaces. Let’s review those furnace types and their efficiency.
This is the simplest furnace. It only has one flame setting. There is no low or medium setting. It is either on or off. A single-stage furnace is cheaper to buy than other more complex models. But they are less efficient, which means they will cost more to operate each month.
Single-stage furnaces allow wide variations in room temperatures. That means if your thermostat is set to 70 degrees, the furnace may not kick in until the temperature in the room falls to 65 degrees. When it does come on, the furnace may heat the room temperature to 72 degrees. The lack of efficiency and stability in room temperature means this single-stage furnace could be more expensive to operate. But in warm climates with very mild temperatures, this type of system may be appropriate because there are so few days when the furnace will be used.
This furnace offers two heat settings, low and high, which provides better efficiency than a single-stage furnace. This furnace will also control room temperatures better than a single-stage. This increased efficiency will cost more than a single-stage furnace to purchase, but the operating costs each month will be less expensive.
Room temperatures will vary less with a two-stage furnace than a single-stage unit. The two-stage furnace could come on when the room temperature drops a couple of degrees cooler than the thermostat, and remain on a couple of degrees beyond. While still a variation on room temperature, the two-stage furnace offers less of a temperature swing than the single-stage unit.
The variable-speed furnace is the most efficient furnace on the market. This furnace maintains room temperature fairly close to the thermostat setting. The furnace changes its heat settings in small increments, creating a relatively stable room temperature.
But the variable-speed furnace is one of the most expensive to purchase and to install. This is not the best choice for every home because the operating costs over time may not be enough to justify the greater upfront cost of the purchase. Some home duct system designs also are not appropriate for the variable-speed furnace.
Is a high-efficiency furnace right for you?
There are homes that may not need high-efficiency furnaces. While the monthly savings on heating bills are nice, are they enough to justify the cost of the variable-speed furnace?
The duct system in your home may not be appropriate for the variable-speed furnace. An undersized duct system may lead to a very loud furnace when it kicks on. The limited ductwork also could reduce your new furnace’s life expectancy, which could impact the overall cost of your home heating.
If you live in a climate where you may turn on the furnace a few nights a year, it is not likely you will recoup the extra cost of buying and installing a high-efficiency furnace. Technological advances in heating and cooling units for residences and businesses will continue to make systems more efficient. You can choose among low- and medium-efficient furnaces that meet the needs of your comfort and budget.
Contact the energy experts at Comfort Systems to discuss what type of furnace works best for your home. The energy professionals can also answer your HVAC design questions. You can also discuss furnace inspection and maintenance options with Comfort Systems to help extend the life of your current system and avoid costly repairs.