Furnaces and Energy Efficiency
Here in the United States, most homes rely on a forced air system to heat and cool your living space.
Gas furnaces, which can be located in a utility closet or laundry room, a basement or crawl space, and even some attics, use natural gas or propane as the fuel source to create heat.
Air is moved across the heat exchanger, which is then "forced" through the ductwork in your home (central air systems usually use the same ductwork as your heating unit).
How Do I Determine Furnace Efficiency?
Modern gas furnaces are all assigned an Annual Fuel Utilization Efficiency (AFUE).
AFUE measures how efficiently your furnace uses its fuel, or energy source. A furnace's AFUE rating is listed as a percentage of how much fuel it converts to viable heat. For example, if a furnace has an AFUE of 88, that means 88% of the energy from the fuel the unit is consuming is usable heat. The other 12% will escape or be ventilated out as exhaust. AFUE is attempting to inform homeowners of the seasonal average efficiency of the unit over time.
How Can AFUE Save Me Money?
Older furnaces can have AFUEs in the lower range, below 70%, which means higher heating costs and lots of wasted fuel. By switching to a new energy-efficient furnace, homeowners can save money on monthly heating bills.
The higher the AFUE number on your high-efficiency furnace, the better your unit is at converting fuel to heat.
So even if a high-efficiency furnace comes with a higher initial price tag, the long term investment will save you money down the road!
Gas Furnaces: Choices
When choosing a new furnace you'll generally have two options for gas furnaces: non-condensing and condensing.
Non-condensing furnaces follow this operation: the burners ignite, the blower motor kicks in, air enters, is filtered, and is blown through the heat exchanger. Heat from the furnace's combustion chamber also goes through the heat exchanger, heats the air, and is forced through the ductwork, eventually venting out through the roof. Non-condensing furnaces are generally at a minimum 80% efficient (or an AFUE of 80).
A condensing furnace uses a second heat exchanger to heat the air from condensed exhaust gases. This second heat exchanger harnesses the energy from the condensed water vapor that usually escapes outside your home and turns it into usable heat. Condensing furnaces tend to use less expensive PVC venting and can have AFUE ratings of 90% and up, so these furnaces are usually more energy-efficient than non-condensing furnaces.
Choosing the Right Furnace
Naturally, less efficient furnaces are usually cheaper than higher efficiency furnaces. Be sure to work with your favorite local HVAC contractor to determine which furnace fits your budget and lifestyle.
Consider how long you plan to stay in your home to determine if you'll recoup your investment costs within your timeframe. High-efficiency furnaces also increase your home's resale value.
Be sure to check with your local authorities to determine if there are cash rebates or breaks on your energy bill for installing high-efficiency appliances.
Outstanding Heating & Cooling would love to work with you to determine if a high or mid-efficiency furnace is right for you! Call us anytime 937-439-4696