Did you know that more than one-half of your home’s energy costs are needed for your heating and cooling? That’s why it’s critical to secure an energy-efficient HVAC system.

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

In 2022, the U.S. government recommended new energy-efficiency standards for residential gas furnaces that would substantially reduce emissions, save consumers money and promote sustainability.

These revised standards are expected to:

  • Save Americans $1.9 billion annually.
  • Cut carbon emissions by 373 million metric tons and methane emissions by 5.1 million tons over the next 25 - 30 years, the equivalent of what 61 million homes emit yearly.

Starting in 2029, the proposed rule would demand 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? Currently, not much, as the proposed rule won't go into effect until 2029 at the earliest and does 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 save you money on your utility 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 limits the quantity of energy wasted, increases energy efficiency and lowers greenhouse gas emissions. It also demands less natural gas to produce the same amount of heat 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 that the former uses a secondary heat exchanger to capture any wasted heat from its exhaust gases, while the other does not.

Equipment Lifespan

The life span of a condensing furnace depends on the brand, model and other factors. Usually, a condensing furnace will last between 10-20 years with proper maintenance and regular service. If you put off scheduled maintenance, the unit may not last as long.

Why Condensing Furnaces Cost More

Usually, condensing furnaces type of system is significantly more efficient than traditional furnaces, as it only consumes the minimum amount of energy required to heat your home, resulting in more savings on your utility bill.

The majority of variable-speed furnaces are condensing furnaces, although a handful are available in non-condensing models with lower AFUE ratings. If a manufacturer wants a furnace to be classified as a condensing furnace, it must offer an AFUE rating of 90% or higher.

Do Variable-Speed Furnaces Run All the Time?

A variable-speed furnace doesn’t operate all the time. Rather, it runs at different speeds according to the temperature in your home as well as the amount of energy it uses to maintain that temperature.

When sufficient energy is required to maintain your preferred temperature level, the furnace will shift to a higher speed in order to keep up with demand. This allows for more efficient heating in your home while also providing quieter operation.

Guide to Two-Stage Furnaces

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

As the name suggests, a furnace with two levels of operating (high or low) is called a two-stage furnace. During the low stage, the furnace performs at a reduced capacity in order to maintain the preferred temperature for your home more efficiently. During the high stage, the furnace will instead run at maximum capacity to meet demands for greater heat. With a two-stage furnace, you can maintain greater energy efficiency and steady 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 operates at limited capacity in order to sustain a desired temperature more efficiently within your home. When more energy is needed to reach the set temperature, the unit will switch to its high stage and operates at full capacity. Because of this, two-stage furnaces are able to help reduce energy costs without operating continuously.

Contrasting Two-Stage and Variable-Speed Furnaces

Two-stage furnaces have two stages of operation, low and high. During the low stage, the furnace runs at reduced capacity in order to sustain a desired temperature within your home. When more warmth or cooling is necessary, the furnace will shift to its high stage and operate at peak capacity.

Variable-speed furnaces, meanwhile, can run at several speeds in order to uphold a more precise temperature 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 of operation and operate either at full capacity or not at all. This means that the furnace is always running in order to maintain a desired level of comfort at home.

Two-stage furnaces, on the other hand, 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 more warmth or cooling is necessary, the furnace will change over to its high stage and operate at peak capacity.

Arrange Your Furnace Install Appointment with Three Rivers Heating & Cooling Today

Making sense of modern furnace technology can be confusing. That’s why Three Rivers Heating & Cooling specialists are here to help with a no-obligation, no-pressure quote for furnace installation. We’ll assess your home, your heating requirements and your budget before helping you find the best solution. Contact us at to get started today!