Skip to content

Are Energy-efficient Furnaces Worth The Extra Money?

Your furnaces energy efficiency ratings let you know your homes electric or gas furnaces energy consumption.

When you buy a brand new heating system or furnace, you must consider the efficiency ratings of a furnace prior to making a decision.

A heating systems energy efficiency rating lets you know the cost of heating your home. High ratings tell you that your unit provides you with more heat from the energy it consumes.

You must also think of fuel costs used for energy before making a purchase. Energy-efficient furnaces, like electric furnaces, are highly efficient, but youll have second thoughts in buying one considering the high cost of electricity nowadays.

Measuring Furnace Efficiency

The AFUE rating, or the Annual Fuel Utilization Efficiency Rating, lets you know the amount of heat produced in comparison to the amount of energy needed to produce that heat. For a furnace that has an 85% AFUE, you lose 15% of the energy, and only converts 85% to heat.

But bear in mind that this computation does not take into consideration heat loss over the duct system. Ductworks that go through the attic can lose as much as 35% of their known heating efficiency. You cant compute this kind of loss since duct systems differ from one home to another.

Older Units That Does Not Have Ratings

Manufacturers are now required by the Federal Trade Commission to include the units AFUE ratings for all new furnaces. However, an older system typically does not have a rating, or it may no longer be there. Observe some guidelines to know the rough estimate of your furnaces efficiency rating.

It is easy to spot a low-efficiency furnace because it comes with a pilot light that must be lit at all times. With this kind of furnace, you must relight its pilot light whenever it goes out. Moreover, they are often based on gravity, depend on drafts, or in the rising of heat, to provide warmth. They are also around 56% up to 70% energy-efficient. There are older furnaces that need the installation of an aftermarket blower, and you can also easily identify them with their octopus-style duct system. A middle-range model has a fan that regulates the airflow. These units utilize an electric ignition, hence, no more pilot light that you need to light up continually. These systems are around 80% to 83% energy efficient. An energy-efficient furnace has two heat exchangers. Meanwhile, condensing units extract water from the exhaust gas before sending the gas over the second heat exchanger for more efficiency. Then, theres the combustion unit that you always seal. They are energy-efficient furnaces with an AFUE rating of 90% up to 95%.

Minimum Furnace Efficiency Standards

A non-condensing furnace must be 78% energy efficient, except units specially indicated for mobile home use. A mobile home unit can have a furnace with a 75% AFUE. The Department of Energy (DOE) increased efficiency standards for a lot of furnace models back in June 2011.

These standards were implemented on May 1, 2013, and on January 1, 2015. After a court ruling issued on January 11, 2013, the Department of Energy temporarily stopped the implementation of the increase in energy standards while waiting for the outcome of the lawsuit.

The following standards are now pending as of May 2013:

* 80% efficiency for non-weatherized gas furnaces.

* 80% efficiency for non-weatherized mobile home furnaces.

* 83% efficiency for non-weatherized oil furnaces.

* 90% efficiency on the installation of all gas furnaces in northern states.

The following standards are pending as of January 2015:

* 81% efficiency for weatherized gas furnaces.

* 78% efficiency for weatherized oil furnaces.

Is a Replacement Furnaces Necessary?

Standards for mobile homes, at 75%, are likely to stay. The same thing goes for electric furnaces at 78%, gas-fired hot water boilers at 82%, oil-fired hot water boilers at 84%, and lastly, oil-fired steam boilers at 82%. A non-weatherized furnace is the furnace of choice for residential use. Meanwhile, a weatherized furnace is best for outdoor use. A homeowner must think about the initial recommendations of the Department of Energy when looking for their homes new furnace. Even though you can buy a cheaper model, youll miss out on big energy savings.


No Trackbacks


Display comments as Linear | Threaded

No comments

The author does not allow comments to this entry

Add Comment

Form options