A gas furnace is still the most common and cost-effective way to heat a home in the northern half of the United States. Natural gas delivers more BTUs per dollar than electricity in most markets, and a modern high-efficiency furnace converts over 96% of that energy into usable heat. After evaluating 12 gas furnaces across efficiency tiers from 80% AFUE single-stage to 97%+ variable-speed, we ranked the five best gas furnaces for 2026.

Best Gas Furnaces at a Glance

ModelAFUEStagesBlower MotorNoise LevelWarranty (Heat Exchanger)Price Range
Trane S9V297%2-stageVariable-speed ECMVery quietLifetime$3,200-$4,500
Carrier Infinity 59MN797%ModulatingVariable-speed ECMVery quietLifetime$3,500-$4,800
Lennox SL297NV97.5%ModulatingVariable-speed ECMUltra-quietLifetime$3,800-$5,200
Goodman GMVC9797%2-stageVariable-speed ECMQuietLifetime$2,200-$3,200
Rheem R97V97%2-stageVariable-speed ECMModerateLifetime$1,800-$2,800

All five units are high-efficiency condensing furnaces that require PVC venting. For a broader comparison of HVAC brands, see our Trane vs Lennox analysis.

Detailed Reviews

Trane S9V2 — Best Overall Gas Furnace

The Trane S9V2 is our top pick for the same reason Trane tops most HVAC reliability surveys: it is built to last. The S9V2 features a two-stage gas valve that runs at approximately 65% capacity on low fire and ramps to 100% only on the coldest days. Paired with a variable-speed ECM blower motor, this means long, gentle heating cycles that distribute warmth evenly without the temperature swings and blower noise of single-stage units.

At 97% AFUE, the S9V2 wastes only 3 cents of every heating dollar — effectively the practical ceiling for gas furnace efficiency. Trane’s stainless steel primary heat exchanger is warranted for life (to the original homeowner), and the secondary (condensing) heat exchanger carries a 10-year warranty. In industry failure data, Trane heat exchangers have among the lowest warranty claim rates of any manufacturer.

The S9V2’s variable-speed blower is one of its strongest features. Unlike a standard PSC blower that runs at one speed, the ECM motor adjusts airflow continuously, which improves comfort, reduces electricity consumption by 50-75% compared to PSC motors, and makes the system nearly silent at low speed. During our evaluation, the S9V2 on low fire was essentially inaudible from the next room.

Trane furnaces are available through authorized Trane dealers, and the quality of installation depends heavily on the dealer. Get quotes from at least two Trane Comfort Specialists in your area and verify they will perform a Manual J load calculation.

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Carrier Infinity 59MN7 — Best Smart Home Integration

The Carrier Infinity 59MN7 is a modulating gas furnace, which means the gas valve adjusts continuously between approximately 40% and 100% capacity rather than switching between two fixed stages. This delivers the finest temperature control of any furnace in our lineup — the 59MN7 can match its output almost exactly to your home’s heat loss at any given moment, which eliminates temperature swings and maximizes efficiency.

At 97% AFUE, the 59MN7 matches the Trane S9V2 on paper efficiency, but the modulating operation gives it a slight edge in real-world gas consumption because it avoids the small efficiency losses that occur during stage transitions. The difference is modest — perhaps 2-3% in annual gas cost — but it compounds over the 20+ year life of the unit.

Where the Carrier really separates itself is in smart home integration. The Infinity system control (Carrier’s proprietary thermostat) connects to the furnace via a serial data link, giving you real-time data on gas valve position, airflow rate, filter status, error codes, and energy consumption. The Carrier Home app provides remote access, maintenance scheduling, and indoor air quality monitoring when paired with Carrier’s air purifier accessories.

The downside is the same as the Carrier AC: the Infinity thermostat is required for full modulating functionality, and the system is only available through authorized Carrier dealers.

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Lennox SL297NV — Quietest Gas Furnace

The Lennox SL297NV holds the highest AFUE rating in our lineup at 97.5%, and it earns our quietest designation with noise levels as low as 41 dB — about the volume of a quiet library. Lennox achieves this through a combination of a modulating gas valve, variable-speed blower, insulated cabinet, and rubber isolation mounts that decouple the blower from the cabinet.

If your furnace is in a closet adjacent to your living space or bedroom, the SL297NV is the clear choice. Most homeowners report that they cannot hear the unit operating on low fire from the next room. Even at full capacity, the SL297NV is noticeably quieter than any other furnace in our roundup.

The 97.5% AFUE rating is 0.5 points above the Trane and Carrier, which translates to roughly $10-$20 per year in gas savings for a typical home. Not a deciding factor, but it does mean the SL297NV wastes less energy than anything else available. The modulating gas valve operates at 250 increments between 40% and 100%, providing extremely fine-grained heat output control.

Lennox’s iComfort thermostat system provides smart home connectivity, though it is not as polished as Carrier’s Infinity system. The lifetime heat exchanger warranty is standard for this tier, and Lennox’s 10-year parts warranty requires dealer registration.

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Goodman GMVC97 — Best Mid-Range Value

The Goodman GMVC97 delivers 97% AFUE efficiency and two-stage heating with a variable-speed blower — the same core feature set as the Trane S9V2 — at a price point $1,000-$1,300 lower. Goodman is owned by Daikin, the world’s largest HVAC manufacturer, which gives the brand genuine engineering resources and manufacturing scale behind its value pricing.

The GMVC97 runs on low fire (roughly 65% capacity) most of the time and ramps to full output when the thermostat calls for more heat than low fire can deliver. The variable-speed ECM blower adjusts airflow to match, keeping noise low and air distribution even. It is not as quiet as the Lennox or as feature-rich as the Carrier, but it provides a meaningfully better heating experience than any single-stage furnace.

Goodman’s standout feature is the lifetime heat exchanger warranty, which covers the tubular aluminized steel heat exchanger for as long as the original homeowner lives in the home. This matches the premium brands and provides substantial peace of mind on the furnace’s most critical component.

The GMVC97 is widely available through independent HVAC dealers, home improvement contractors, and wholesale distributors. This wide availability also means competitive installation pricing and easy access to replacement parts.

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Rheem R97V — Best Budget Gas Furnace

The Rheem R97V proves you do not need to spend $4,000+ to get a 97% AFUE furnace. At $1,800-$2,800 for the unit, the R97V is the most affordable high-efficiency furnace in our lineup, and it includes a two-stage gas valve and variable-speed ECM blower — features you would not have found at this price point even two years ago.

Rheem manufactures the R97V at its Montgomery, Alabama facility and sells through independent contractors, making it widely available and competitively priced for installation. The heat exchanger carries a lifetime warranty (with registration and documented maintenance), and the remaining parts are covered for 10 years.

Performance is solid. The two-stage gas valve and variable-speed blower provide the expected comfort improvements over single-stage units — longer, quieter cycles, more even heating, and better air mixing. The R97V is not as refined as the Trane or Carrier in terms of noise dampening or blower control precision, but the difference is marginal in a typical installation where the furnace is in a basement, utility closet, or garage.

For homeowners replacing an aging 80% AFUE furnace, the R97V is an easy recommendation. The 17-point AFUE improvement alone saves $200-$400 per year in gas costs, which means the new furnace pays for itself in 5-8 years through energy savings alone.

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Gas Furnace Efficiency Explained

AFUE: What the Number Means

AFUE (Annual Fuel Utilization Efficiency) measures what percentage of the gas your furnace burns gets converted to usable heat. A 97% AFUE furnace converts 97 cents of every dollar of natural gas into heat for your home, with 3 cents lost through exhaust gases.

Gas furnaces fall into two categories:

Conventional (80-83% AFUE): These use a single metal heat exchanger and vent hot exhaust gases through a metal flue pipe. They are less efficient because usable heat escapes with the exhaust. The federal minimum is 80% AFUE.

Condensing (90-98% AFUE): These add a secondary heat exchanger that captures additional heat from exhaust gases by cooling them to the point where water vapor condenses. The condensation process releases latent heat, boosting efficiency by 10-18 points. Condensing furnaces vent through PVC pipe (the exhaust is cool enough for plastic) and require a condensate drain.

All five furnaces in our roundup are condensing units at 97% or above. If you are currently running an 80% AFUE furnace, upgrading to any of these units will cut your gas consumption by roughly 17-18% immediately.

Gas Furnace vs Heat Pump

Natural gas furnaces and electric heat pumps serve the same function — heating your home — through fundamentally different mechanisms. A furnace burns fuel to generate heat directly. A heat pump moves heat from outside air into your home using a refrigerant cycle, producing 2-4 units of heat energy per unit of electricity consumed.

The economics depend on your local gas and electricity prices. At national average rates ($1.20/therm for gas, $0.16/kWh for electricity), a gas furnace costs roughly 30-40% less to operate than an electric heat pump in cold climates (zones 5-7). In mild climates (zones 1-3), heat pumps can be cheaper because they run more efficiently in moderate temperatures.

For a detailed climate-specific comparison, see our best heat pumps by climate zone guide.

Installation Considerations

Venting Requirements

Every furnace in our roundup is a condensing unit that vents through PVC pipe, not a traditional metal chimney flue. If you are replacing a conventional (80% AFUE) furnace, the installer will need to run new PVC intake and exhaust pipes, usually through a side wall. This adds $300-$800 to the installation cost but is a one-time expense.

The PVC pipes must terminate at least 12 inches above grade, 4 feet below any window or door, and 3 feet from any gas meter or regulator. Improper venting is the leading cause of carbon monoxide incidents with condensing furnaces, so this is not a detail to cut corners on.

Gas Line Sizing

High-efficiency furnaces with large BTU ratings (100,000+ BTU) may require a gas line upgrade if your existing line was sized for a smaller unit. An undersized gas line causes the furnace to underperform and can trigger pressure-related error codes. Your installer should verify gas line capacity as part of the load calculation.

Condensate Management

Condensing furnaces produce 1-3 gallons of condensate (acidic water) per hour during operation. This condensate must drain to a floor drain, condensate pump, or exterior drain point. In freezing climates, exterior drain lines need heat tape or must be routed to an interior drain to prevent ice blockage. Budget $100-$300 for a condensate pump if no floor drain is nearby.

Maintenance for Maximum Lifespan

For a complete seasonal checklist, see our HVAC maintenance guide.