AFUE is one of the most important measures for heating appliances, including furnaces, boilers, or water heaters. But what exactly does AFUE mean, and what does an AFUE rating tell you about your equipment?
An AFUE (Annual Fuel Utilization Efficiency) rating – often displayed on a yellow sticker on the unit – is an efficiency measure that represents the amount of fuel that is consumed by your equipment compared to the amount of energy produced by the equipment over the course of a year.
Here’s an example: in a 90 AFUE furnace unit, 90 percent of the fuel consumed by the machine results in heat for your home; the other 10 percent is lost somewhere in the delivery chain (usually up the flue).
A useful way to think about AFUE is to consider it in terms of money: For every dollar you spend on heating oil or propane for an 80 AFUE boiler, 80 cents go toward heating your home’s air; In a 95 AFUE furnace, that number jumps up to 95 cents – a big difference on your monthly bills.
What’s a typical AFUE rating for a furnace? That depends on how old your unit is, and what fuel powers it. Older, less efficient furnaces have considerably lower AFUE ratings than new models – especially if they have not been properly maintained by a heating professional. Gas furnaces also tend to have higher AFUE ratings than oil-fired furnaces, because gas burns cleaner.
Here are some efficiency guidelines for typical furnaces according to the U.S. Department of Energy:
As of 2015, the minimum standard AFUE for new furnaces Is 80 percent.
Of course, AFUE doesn’t tell the whole heating efficiency story – the air tightness of your home, how well you maintain your equipment, the condition of your ducts, and how well your heating equipment was installed all come into play when determining how much heating bang you get for your buck.
For these reasons and more, it always pays to hire a professional to install, maintain, and repair your furnace.
Looking for an energy efficient replacement for your furnace? We can help! Contact Holden Oil today for a FREE, no obligation estimate on a furnace installation in the North Shore of Massachusetts!