Types of AFUE Ratings for Forced Air Furnaces

Man fixing furnace

You currently have different options for indoor heating when picking your heating ventilation and air conditioning unit. One of the most energy efficient and convenient alternatives you can choose is a forced-air furnace.

This can either run on oil or natural gas which is inexpensive and readily available in most regions. Forced-air furnaces have different blower stages and settings, which determine their operation. There are different elements which will determine the efficiency of your furnace.

One of these is the type of HVAC installation you pick for your Herriman property. Most people opt for DIY installation since this is inexpensive.

This is, however, the primary factor which leads to their furnace’s energy wastage and poor operation since there are many mistakes in the furnace’s installation. Other than an expert installation, you should pay attention to the AFUE rating of your furnace to guarantee its energy efficiency.

This rating denotes the fuel quantity needed by your furnace to generate heat in different seasons and with different loads. Here are the four categories of AFUE ratings you will find when shopping for your furnace.


This AFUE rating denotes that your furnace only converts 55–72% of the energy supplied for heating. This is an obsolete AFUE rating which was used in furnaces long ago.

Some dealers might however still stock furnaces with a 55–72% rating to fool property owners who are none the wiser. Moreover, there are still some property owners who have furnaces with this rating more so those in old properties.


This rating indicates only 78% of the energy in your furnace is converted to heat. This was the minimum furnace efficiency rating allowed by the government up until January 2015. Since then, more energy efficient furnaces have come up, and it is prudent to upgrade yours if you bought your furnace before this time.


This rating is found in mid and standard efficiency furnaces. Some, however, can have a score as high as 89% depending on the manufacturer. The minimum recommended AFUE rating by the government is 80% for gas furnaces

Unlike low-efficiency models, mid-efficiency furnaces have an electronic ignition, which does not waste energy. They also come with variable speed blowers which are more energy efficient than single-speed fans.


pipes of a furnace

This denotes the most energy efficient furnace on the market currently. In most states, these furnaces have energy star approval. Unlike other furnaces, high-efficiency furnaces with a 90–98% AFUE rating are condensing rather than conventional furnaces.

They are available as two-stage, single or modulating furnaces. Although expensive they will save you a tidy sum in energy costs.

Unlike in the past, almost all appliances in your property are now automated. A huge chunk of your property’s operation costs now thus goes into energy costs for running these appliances. Because of this, most property owners would shun furnaces to save on their monthly energy costs.

Luckily, you don’t need to be one of the people who contend with freezing indoors due to high energy costs. The information above will guarantee you make the proper AFUE rating choice to meet your property’s heating needs without unnecessarily increasing your energy bills.

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