Would you believe that more than half of your home’s energy costs are needed for your heating and cooling? That’s why it’s so important to maintain an energy-efficient HVAC system.

Furnace efficiency standards were last updated to an Annual Fuel Utilization Efficiency (AFUE) rating of 80% in 2015. This rating system illustrates how effective your furnace is at natural gas into heat. An AFUE rating of 80% means your furnace wastes about 20% of the fuel it uses while generating heat.

In 2022, President Biden revealed new energy-efficiency standards for residential gas furnaces that would significantly decrease emissions, save homeowners money and encourage sustainability.

These revised standards are projected to:

  • Save Americans $1.9 billion annually.
  • Reduce carbon emissions by 373 million metric tons and methane emissions by 5.1 million tons over 30 years, the equivalent of what 61 million homes emit each year.

Starting in 2029, the updated rule would require all new gas furnaces to feature AFUE ratings of 95%. This means furnaces would combust nearly 100% of the gas into usable heat.

Considering these guidelines, you might be asking yourself what does that mean for my existing furnace? For the time being, next to nothing, as the proposed rule won't go into effect until 2029 at the earliest and will not affect furnaces that are already in use.

But if you need furnace replacement in soon, highly energy-efficient furnaces are now available. Learn how these furnaces can lower your monthly energy bills.

Guide to Condensing Furnaces

How Condensing Furnaces Work

A condensing furnace is a type of heating system that uses a secondary heat exchanger to trap wasted heat from the furnace's exhaust gases. This decreases the amount of energy wasted, increases energy efficiency and lowers greenhouse gas emissions. It also demands less natural gas to generate the same rate of heat when compared to other types of furnaces.

How Condensing Furnaces Differ from Non-Condensing Furnaces

The primary difference between a condensing furnace and a non-condensing furnace is condensing models use a secondary heat exchanger to gather any wasted heat from its exhaust gases, while the other does not.

How Long Condensing Furnaces Last

The life span of a condensing furnace depends on the brand, model and other factors. Usually, a condensing furnace should last between 10-20 years with sufficient maintenance and regular service. If your heating system doesn’t have regular furnace maintenance, the unit may have a significantly shorter life span.

Why Condensing Furnaces Cost More

For the most part, condensing furnaces type of system is a lot more efficient than traditional furnaces, as it only uses the minimum amount of energy required to heat your home, which  subsequently saves money on your utility bills.

Many variable-speed furnaces are condensing furnaces, although a handful are available in non-condensing models with lower AFUE ratings. In order for a furnace to be classified as a condensing furnace, it must offer an AFUE rating of 90% or higher.

Do Variable-Speed Furnaces Run Constantly?

A variable-speed furnace doesn’t run all the time. Alternatively, it runs at different speeds based on the temperature in your home as well as the amount of energy it uses to sustain that temperature.

When sufficient energy is demanded to maintain your set temperature level, the furnace will increase to a higher speed in order to keep up with demand. Doing this will ensure more efficient heating in your home while also offering quieter operation.

Guide to Two-Stage Furnaces

Two-Stage Furnaces: What They Are and How They Work

A heating system with two settings of operating - high and low - is called a two-stage furnace. On the low stage, the furnace operates at a reduced capacity as a way to maintain the desired temperature in your home more efficiently. During the high stage, the furnace will instead operate at full capacity to satisfy demands for more heat. With a two-stage furnace, you can enjoy greater energy efficiency and consistent temperatures everywhere in your home.

While two-stage furnaces are highly efficient, not all all models are condensing furnaces.

Does a Two-Stage Furnace Operate All the Time?

A two-stage furnace won’t run all the time. In the low stage of operation, the furnace runs at reduced capacity in order to maintain a preferred temperature more efficiently within your home. When a greater demand for energy is needed to reach the set temperature, the furnace will switch to its high stage and runs at full capacity. For this reason, two-stage furnaces are powerful enough to help reduce energy costs without operating continuously.

Comparing Two-Stage and Variable-Speed Furnaces

Two-stage furnaces have two stages of functionality, low and high. During the low stage, the furnace works at reduced capacity in order to maintain a desired level of comfort within your home. When more warmth or cooling is desired, the furnace will change over to its high stage and operate at maximum capacity.

Variable-speed furnaces, meanwhile, can work at several speeds in order to maintain a desired temperature more consistently at home. Such precise functionality can also help reduce energy costs, as it is not constantly running on full power like many two-stage furnaces do.

Differences Between One- and Two-Stage Furnaces

One-stage furnaces have a single stage fan speed and operate either at full power or not at all. As a result, the furnace is always running in order to maintain a desired comfort level within your home.

Two-stage furnaces, by comparison, have two stages of operation, low and high. While in the low stage, the furnace runs at [lower|reduced} capacity in order to maintain the desired temperature more efficiently. When additional warmth or cooling is necessary, the furnace will change over to its high stage and operate at peak capacity.

Schedule Your Furnace Installation with Temperature Doctors Heating & Cooling Today

It takes experience and dedication to stay up to date about furnace technology advancements. That’s why Temperature Doctors Heating & Cooling professionals are here to help with a free, no-pressure estimate for furnace installation. We’ll assess your home, your heating requirements and your budget before helping you find the ideal solution. Call us at to get started today!