Upgrade To A High Efficiency Gas Furnace
A high efficiency furnace is a heating system designed to convert 90% or more of its fuel into heat for your home. By wasting significantly less energy than older, standard models, a high efficiency gas furnace can help lower heating bills, reduce environmental impact, and provides more consistent indoor comfort.
According to the Department of Energy, heating your home typically represents about 45% of your utility bill. [1] That’s a significant investment. When it comes to furnaces, “efficiency” refers to how effectively they can convert heating energy from a fuel source into warm, comfortable heat for your home. Today’s highest efficiency furnaces can provide comfort with up to 98.5% AFUE efficiency.
What is a High Efficiency Gas Furnace?
A high efficiency gas furnace is defined by an AFUE rating of 90% or higher, reaching up to a maximum of 98.5% AFUE.
AFUE stands for Annual Fuel Utilization Efficiency. It measures how much heat the furnace captures from the fuel it consumes. For example, a 95% AFUE furnace converts 95% of the fuel into heat and only wastes 5%. This rating is determined by measuring the heat in British Thermal Units (BTU) compared to the fuel used.
The Department of Energy requires all manufacturers to display a furnace’s efficiency on a yellow Energy Guide sticker. Efficiency standards evolve, so investing in high efficiency furnaces now prepares your home for future standards.
Why Choose a High Efficiency Gas Furnace?
Kevin Dickson, president of Energy Services Air Conditioning, Heating and Electrical in Naperville, Illinois, explains the major selling points for homeowners:
“The top reason that a homeowner should consider a high-efficiency furnace is the potential for energy savings, which means lower heating bills.. High-efficiency furnaces also provide additional safety due to the sealed combustion that brings in outdoor air. They also often qualify for rebates with local utility companies.”
Benefits of Upgrading
- Cost Savings: Because these models excel at converting fuel into heat, you need less fuel to maintain comfort.
- Environmental Impact: Higher efficiency results in fewer emissions.
- Enhanced Comfort: Many Carrier high efficiency furnaces include technology that produces quieter operation and more consistent temperatures.
- Safety: Sealed combustion systems use outdoor air, improving safety and indoor air quality.
Is a High Efficiency Furnace Worth the Investment?
Replacing your old heating equipment with a new, high efficiency gas furnace often makes financial sense.
Older heating systems may operate at 56–70% AFUE efficiency, which falls far below today’s standards. In contrast, modern high efficiency models operate in the 90–98.5% AFUE range. Since heating is likely the largest expense on your utility bill, this upgrade offers a clear path to savings.
Long-Term Value vs. Upfront Cost
While high efficiency furnaces often come with higher price tags, the initial difference is typically offset by reduced heating bills over the life of the equipment. A new system also offers higher reliability and fewer costly furnace service calls compared to an aging system that is likely to falter during a cold snap.
As you consider your options, look into the cost of a new furnace, have a reputable HVAC contractor estimate energy costs, and factor in potential repairs for your current system.
Note: This article compares select fuel sources. Other systems, like air-source heat pumps and geothermal systems, operate differently. Learn more about a heat pump vs. furnace.
High Efficiency Oil Furnaces vs. Gas
High efficiency oil furnaces can cost less to operate per BTU generated than other types, but they typically max out at an AFUE rating of about 86.6%.
Compared to the 90–98.5% ratings of natural gas furnaces or 100% ratings of electric furnaces, oil is less efficient. However, in regions without access to natural gas pipelines, the highest efficiency oil furnace remains a viable, powerful option for home heating.
Comparing Energy Efficient Heating Types
Forced air furnaces generally work on the same principle: heat is extracted in a heat exchanger and circulated through ducts. However, the fuel source dictates the efficiency and cost.
Natural Gas Furnace
Natural gas is the most common heating source in the U.S. [2]. It is widely available and generally the least expensive per BTU. Consequently, a high efficiency gas furnace (90–98.5% AFUE) can significantly lower monthly costs. Browse the best Carrier furnaces to see options for every budget.
Electricity
Electric furnaces are technically 100% efficient at converting energy to heat. However, electricity is often more expensive than natural gas or propane, leading to higher operating costs in many regions.
Fuel Oil
Common in the Northeast U.S., fuel oil requires a storage tank and delivery. While less efficient than gas (topping out around 86.6% AFUE), newer models can sometimes use cleaner-burning biodiesel mixtures.
Propane Furnaces
Propane is a clean-burning alternative to oil. While Carrier does not manufacture dedicated propane furnaces, our furnaces can be converted by a professional technician for use with propane.
What Features Define High Efficiency Furnaces?
An energy efficient furnace squeezes extra heat from fuel using advanced technology not found on standard models.
- Secondary Heat Exchangers: To achieve 90% AFUE, a furnace typically uses two heat exchangers. The primary captures the first 80%, while the secondary pulls remaining heat from combustion gases.
- Greenspeed® Intelligence: Found in Infinity Series gas furnaces, this integrates variable-speed blower motors and modulating gas valves to match heating capacity to current conditions.
- ComfortFan™ Technology: Allows you to control fan speeds for optimized air circulation.
- Sealed Combustion: Pulls air from outside for combustion, improving safety and efficiency.
Ready to improve your home's comfort? Connect with a local Carrier furnace expert to schedule a gas furnace upgrade or furnace maintenance.
Frequently Asked Questions
Standard-efficiency furnaces typically have an AFUE of 80%, meaning 20% of the fuel energy is wasted. A high efficiency furnace has an AFUE of 90–98.5%, utilizing secondary heat exchangers to capture more heat and waste significantly less fuel.
The installed cost generally ranges from $3,800 to $12,000. High efficiency furnaces sit at the higher end of this scale due to advanced technology, but they offer greater long-term savings on operating costs.
According to the Department of Energy, upgrading from 80% to 95% efficiency can save around $73 annually, though this varies by climate and usage. [3] Payback is calculated by subtracting rebates from the installed cost, then dividing by annual energy savings.
Yes, investing in a high efficiency gas furnace can be worth it for many homeowners planning to stay in their homes for several years. The reduced monthly energy bills, improved comfort, and potential for rebates help offset the initial investment, particularly in colder climates where the furnace runs frequently.
Gas furnaces require access to a natural gas line, which isn't available in all areas. They also require professional installation and strict adherence to safety protocols regarding ventilation and carbon monoxide. However, for most homes with gas access, they remain the most cost-effective heating solution.
About The Author: Ryan Mayes is a Senior Digital Brand Marketing Manager at Carrier who focuses on creating clear, helpful resources on HVAC topics. Ryan’s goal is to guide readers toward smart, confident decisions about their indoor comfort.