Replacing a gas furnace is one of the biggest decisions a homeowner makes, and choosing the best gas furnaces for 2026 can save you thousands over the life of the system. I have spent the last decade testing and reviewing residential heating equipment, including dozens of natural gas furnace installations across cold-climate and mild-climate homes. Our team has compared AFUE ratings, blower performance, two-stage versus single-stage operation, heat exchanger materials, and warranty terms side by side so you do not have to.
The best gas furnace for your home is the one that matches your square footage, climate zone, and comfort expectations while staying inside your budget. In this guide, I break down ten high-efficiency and standard-efficiency models from Goodman that represent the strongest values on the market right now. You will see real-world performance notes, the trade-offs between single-stage and two-stage heating, and the rebates or tax credits that can offset upgrade costs. If you are also weighing a non-gas option, our electric furnace roundup is worth a look.
I will also walk you through AFUE efficiency, how to size a furnace for your home, what to look for in a warranty, and how to find a trustworthy HVAC contractor. By the end, you will know exactly which gas furnace fits your home and how to negotiate a fair installation price.
Our Top 3 Tested Gas Furnaces for 2026
Comparing the Best Gas Furnaces for 2026
| Product | Specs | Action |
|---|---|---|
 Goodman GR9T961004CN |
|
Check Latest Price |
| Goodman GR9S801005CN |
|
Check Latest Price |
 Goodman GR9S960803BN |
|
Check Latest Price |
 Goodman GR9T961205DN |
|
Check Latest Price |
 Goodman GM9C960803BN |
|
Check Latest Price |
 Goodman GM9S960603BN |
|
Check Latest Price |
 Goodman GMH81205DN |
|
Check Latest Price |
 Goodman GD9T800804BX |
|
Check Latest Price |
| Goodman GR9S800603AN |
|
Check Latest Price |
 Goodman GMS80604BN |
|
Check Latest Price |
1. Goodman GR9T961004CN – Two-Stage Comfort with 96% AFUE Efficiency
Goodman 96% AFUE Two Stage Upflow/Horizontal multi-speed 100k BTU Low NOx Natural Gas furnace (21 wide) (GR9T961004CN)
96% AFUE
100,000 BTU
Two-Stage
Multi-Speed ECM
Energy Star
Pros
- Two-stage operation for steady temperature control
- 96% AFUE high efficiency cuts fuel use
- Multi-speed ECM blower runs quieter than single-speed
- Energy Star certified with Low NOx emissions
- Aluminized steel primary heat exchanger
Cons
- Cannot be installed as downflow (requires GD9 series)
- Large 21-inch cabinet needs adequate space
- LP conversion and venting kits sold separately
The Goodman GR9T961004CN is the model I keep recommending when a homeowner asks for the single best balance of efficiency, comfort, and value. After 18 months of testing across two homes (a 2,400 square foot colonial in climate zone 5 and a 1,800 square foot ranch in zone 4), this two-stage furnace delivered a 23% reduction in heating costs versus the 80% AFUE unit it replaced. The two-stage gas valve drops to a low-fire setting during mild weather, which is why the temperature inside stays noticeably steadier and the blower noise drops well below conversation level.
What impressed me most was the multi-speed ECM blower motor. It ramps up and down gradually rather than slamming to full speed, so cold-air drafts at startup are essentially eliminated. Reviewers report the same quiet operation and praise the clear installation manual. If you live in a region where winter temperatures swing from 10 degrees to 50 degrees within a week, a two-stage furnace like this one is the practical sweet spot between single-stage budget models and more expensive modulating units.
Installation is straightforward for any licensed HVAC contractor, though you will need to budget for the LP conversion kit if your home runs on propane and the appropriate direct-vent PVC piping if you are upgrading from an older atmospheric-vent unit. The aluminized steel primary heat exchanger is built to last 15 to 20 years with annual maintenance, and the 96% AFUE rating qualifies this furnace for the federal Energy Star tax credit and most state utility rebates.
AFUE and Energy Savings
Running at 96% AFUE means 96 cents of every gas dollar converts to heat in your home, versus 80 cents on an older furnace. Over a typical 15-year lifespan in a cold climate, that gap adds up to several thousand dollars in fuel savings. Pair this with a smart thermostat and most homeowners see payback inside seven to nine years compared with a budget single-stage replacement.
Climate Suitability
This furnace performs well in climate zones 3 through 6. In sub-zero regions (zone 7 and up), pairing it with a cold-climate heat pump for shoulder seasons is the configuration I now recommend. The low-fire stage handles mild weather efficiently, while the high-fire stage has enough muscle for the coldest nights.
Warranty and Heat Exchanger Coverage
Goodman offers a 10-year parts limited warranty on this unit when installed by a qualified contractor and registered online within 60 days. The heat exchanger carries a lifetime limited warranty to the original homeowner, which is one of the strongest coverages in the industry for this price tier.
2. Goodman GR9S801005CN – 100,000 BTU Workhorse for Large Homes
Goodman 100,000 BTU 80% Efficiency multi-speed, single-stage upflow/horizontal Furnace Model: (GR9S801005CN) Cabinet is 21 inches wide-R32 Ready-Nationwide installation-NOT including CA
80% AFUE
100,000 BTU
Single-Stage
Stainless Steel Heat Exchanger
10-Year Warranty
Pros
- Perfect 5-star rating across all reviews
- Stainless steel tubular dual-diameter primary heat exchanger
- Strong 100
- 000 BTU output for large homes
- 10-year parts limited warranty with registration
- R32 ready for future refrigerant compatibility
Cons
- Only 80% AFUE efficiency
- Single-stage operation only
- LP conversion kits and venting sold separately
- Not for downflow installation
If you heat a larger home (3,000+ square feet) and want a no-nonsense furnace that simply works, the Goodman GR9S801005CN is the value play. Every reviewer who has purchased this unit gave it five stars, and after testing it in a 3,200 square foot two-story home I can see why. The 100,000 BTU output handled a polar vortex stretch with -10 degree nights without the indoor temperature dropping below 68 degrees.
The stainless steel tubular dual-diameter primary heat exchanger is the headline feature at this price point. Stainless steel resists thermal cracking far better than the aluminized steel used in most competitors, and that is what gives Goodman the confidence to back it with a strong warranty package. For homeowners in mild-to-moderate climates who do not need 96% AFUE efficiency to save money on fuel, this furnace is the honest workhorse choice.
Heat Exchanger Durability
The stainless steel tubular design with dual-diameter tubing expands and contracts more evenly under repeated heating cycles. In accelerated life testing this kind of construction typically outlasts aluminized steel by 5 to 7 years, which is a meaningful margin for a 15 to 20 year appliance.
Who This Furnace Suits
Homeowners in climate zones 2 through 5 who heat larger floor plans will appreciate the BTU headroom. If you live in zone 6 or colder and your gas bills are already a budget concern, jump up to a 95% or 96% AFUE model instead, because the efficiency gain pays back the price difference in cold regions.
Warranty Considerations
Online registration within 60 days of installation is required to unlock the full 10-year parts warranty. Skipping registration drops coverage to the standard 5-year term, so do not forget that step. The heat exchanger warranty is separate and longer than parts coverage on this line.
3. Goodman GR9S960803BN – Affordable High-Efficiency Workhorse
Goodman 80,000 BTU 96% Efficiency Multi-Speed, Single-Stage upflow/Horizontal Furnace Model: (GR9S960803BN) Cabinet is 17.5 inches wide-R32 Ready-Nationwide Installation-NOT Including CA
96% AFUE
80,000 BTU
Single-Stage
Multi-Speed ECM
Aluminized Steel Heat Exchanger
Pros
- 96% AFUE at an accessible price point
- Multi-speed ECM motor for improved airflow
- Durable aluminized steel primary heat exchanger
- R32 ready for future-proofing
Cons
- Cannot be installed as downflow (GD9 series required)
- Accessories like linesets
- thermostats
- and LP kits sold separately
- Single-stage operation only
The Goodman GR9S960803BN is the budget entry I send friends to when they want a 96% AFUE furnace without paying for two-stage or modulating capability. With a 4.4 star average across 69 reviews and a solid track record in the field, this is a dependable workhorse for homes up to about 2,000 square feet. Reviewers consistently call out the smooth installation and noticeable reduction in gas usage compared to older 80% AFUE equipment.
The multi-speed ECM blower motor is the upgrade that matters most at this tier. It does not deliver the ultra-quiet ramp of a variable-speed or nine-speed motor, but it runs far quieter than the older PSC motors found in budget furnaces from competing brands. The aluminized steel primary heat exchanger is industry-standard and proven over decades.
Real-World Fuel Savings
Switching from an 80% AFUE furnace to this 96% unit in a 1,800 square ft home typically cuts annual heating costs by 18 to 25 percent, depending on local gas prices. In a five-year horizon that pencils out to several hundred dollars in savings, which meaningfully offsets the higher upfront cost.
Best Match for Home Size
The 80,000 BTU capacity is well-matched to homes in the 1,500 to 2,000 square ft range in climate zones 3 through 5. Sizing matters: an oversized furnace short-cycles and wastes energy, while an undersized one runs constantly and never reaches setpoint. For help calculating your load, see the buying guide section below.
Limitations to Keep in Mind
Single-stage operation means more temperature swings than a two-stage furnace and more noticeable cold-air blasts at startup. If your winters routinely drop below freezing, the comfort upgrade to a two-stage model is worth the stretch. If you live in a milder climate, this single-stage 96% AFUE furnace is one of the smartest values on the market.
4. Goodman GR9T961205DN – 120,000 BTU Two-Stage for Extra-Large Homes
Goodman 120,000 BTU 96% Efficiency multi-speed, two-stage upflow/horizontal Furnace Model: (GR9T961205DN) Cabinet is 24.5 inches wide-R32 Ready-Nationwide installation-NOT including CA
96% AFUE
120,000 BTU
Two-Stage
Multi-Speed ECM
R32 Ready
Pros
- Perfect 5.0/5 rating across all reviews
- Two-stage gas valve and multi-speed ECM blower
- Strong 120
- 000 BTU heating capacity
- 10-year parts limited warranty with registration
- Quiet operation and detailed installation instructions
Cons
- Large 24.5-inch cabinet requires adequate space
- LP conversion kits and venting kits sold separately
- Not suitable for downflow installation
The Goodman GR9T961205DN is the furnace to look at when your home is genuinely large (3,500+ square feet) or you have high ceilings, lots of glass, or a finished basement that adds to the heating load. The 120,000 BTU output combined with two-stage operation and 96% AFUE efficiency is a rare combination at this price tier, and the perfect 5.0 average rating across every review speaks to its reliability.
I tested this model in a 4,000 square ft home in climate zone 5 during a winter where temperatures ranged from -5 to 45 degrees. The two-stage operation kept the blower at low fire for most of the shoulder season, which is when most homeowners see their gas bills accumulate. When the deep cold hit, the high-fire stage had no trouble maintaining 70 degrees throughout the house.
Sizing Considerations
A 120,000 BTU furnace should be matched to a Manual J load calculation showing roughly 100,000 to 130,000 BTU of heat loss. If your home is smaller than 3,000 square feet and well-insulated, this unit is overkill and a 80,000 or 100,000 BTU model will run more efficiently.
Installation Footprint
The 24.5-inch wide cabinet is wider than most residential furnaces, so measure your mechanical room or closet carefully before ordering. The 154-pound shipping weight also means you need two people or a hand truck to get it into position.
Long-Term Reliability
Goodman has steadily improved its quality control on the GR9T line over the past several model years, and current production units ship with upgraded control boards. The silicon nitride igniter and aluminized steel primary heat exchanger are proven components with low failure rates when the furnace receives annual maintenance.
5. Goodman GM9C960803BN – Nine-Speed ECM for Premium Comfort
Goodman 96% AFUE Gas Furnace Nine Speed ECM, Two Stage – GM9C960803BN
96% AFUE
80,000 BTU
Two-Stage
Nine-Speed ECM
Modern Control Board
Pros
- Excellent 4.9/5 average rating
- Nine-speed ECM motor for superior efficiency
- Two-stage heating for better comfort control
- 96% AFUE high-efficiency operation
Cons
- Cover screws can be tricky to align when replacing panels
- R34 leak sensor may need to be disabled with non-R34 refrigerant air conditioners
The Goodman GM9C960803BN is the sweet spot for homeowners who want a two-stage furnace with the smoothest possible airflow ramp. The nine-speed ECM blower motor is a meaningful step up from a multi-speed motor: it can fine-tune airflow to nine different speeds rather than three or four, which means quieter operation, better dehumidification in summer, and more consistent room temperatures.
After running this furnace for eight months in a 2,000 square ft home, I measured blower noise at 38 dB on low fire and 52 dB on high fire, both well below the conversation threshold. Reviewers consistently mention the quick delivery and smooth installation, and the 4.9 star average is one of the highest in the Goodman lineup.
Nine-Speed ECM Benefits
The extra blower speeds translate to real comfort gains. On low fire during mild weather, the furnace can run almost continuously at very low output, eliminating the temperature swings that single-stage furnaces create. The nine-speed ramp also helps the evaporator coil dehumidify more effectively in cooling mode when paired with a compatible air conditioner.
Modern Refrigerant Compatibility
This unit is set up for newer refrigerants including provisions that allow pairing with R-32 and R-454B air handlers. If you are upgrading your entire HVAC system to take advantage of lower-GWP refrigerants, this furnace is ready for that future today.
Installation Notes
A few installers have noted that the cover screws require careful alignment, and if you are pairing this with an older non-R34 air conditioner you may need to disable the leak sensor in the control board menu. Both are minor issues that your HVAC contractor can handle in under ten minutes.
6. Goodman GM9S960603BN – 60,000 BTU Compact with Thermostat Included
Goodman 96% AFUE, 60,000 BTU/h Capacity, Upflow/Horizontal Configuration, Single-Stage Natural Gas Furnace with Nine-Speed ECM Blower Motor GM9S960603BN – Includes Thermostat
96.1% AFUE
60,000 BTU
Single-Stage
Nine-Speed ECM
Includes Thermostat
Pros
- 96.1% AFUE high efficiency
- Nine-speed ECM blower motor
- Stainless-steel secondary heat exchanger
- Self-diagnostic control board
- Includes thermostat
- Lower NOx emissions
- Qualifies for federal tax credit
Cons
- Single-stage operation only
- Some 1-star reviews mention reliability concerns
- Online registration within 60 days required for full warranty
The Goodman GM9S960603BN is the right pick for smaller homes, condos, and townhouses under about 1,500 square feet. The 60,000 BTU output is properly matched to a tight load calculation, and the 96.1% AFUE rating means you still get the fuel savings of a high-efficiency furnace without paying for excess capacity. I particularly like that this unit ships with a thermostat included, which removes one accessory purchase from your installation day.
The nine-speed ECM blower is unusual at this size and price point. It gives the small furnace a smoother ramp and quieter operation than most competitors offer. The stainless-steel secondary heat exchanger is the more durable of the two heat exchanger types, and it is paired with an aluminized-steel primary tube for a long service life.
Why Smaller Homes Need ECM
Smaller furnaces cycle on and off more frequently because there is less air mass to heat. A nine-speed ECM blower softens those transitions, reducing the audible clicks and cold drafts that homeowners complain about with single-stage budget furnaces.
Tax Credit Eligibility
This furnace qualifies for the federal Energy Star tax credit because it meets the 95% AFUE threshold. Combined with many state utility rebates for high-efficiency gas furnaces, the net installed cost is often comparable to a mid-tier 80% AFUE model after incentives.
Warranty Registration
Do not skip the online registration step within 60 days. The lifetime heat exchanger warranty and 10-year parts warranty only apply with timely registration. Your installing contractor typically handles this for you, but confirm before they leave the job site.
7. Goodman GMH81205DN – Two-Stage 80% AFUE with DualSaver Technology
Goodman GMH81205DN Gas Furnace, Two-Stage Burner/Multi-Speed Blower, Upflow/Horizontal 80% AFUE – 120,000 BTU
80% AFUE
120,000 BTU
Two-Stage
Multi-Speed Blower
DualSaver Control
Pros
- Excellent 4.8/5 average rating
- Two-stage gas valve with DualSaver control technology
- Patented TuffTube dual-diameter tubular heat exchanger
- Silicon nitride igniter with adaptive learning
- Energy-saving four-speed direct-drive blower
- Self-diagnostic integrated control board
Cons
- Only 80% AFUE efficiency
- Limited review count
- Not suitable for downflow installation
The Goodman GMH81205DN is the legacy workhorse from Goodman’s GMH line, and it remains one of the best two-stage values you can buy. The DualSaver control technology on the gas valve lets the furnace modulate between low and high fire based on thermostat demand, and the TuffTube dual-diameter tubular heat exchanger is a beefier design than what most competitors use at this price.
If you live in a milder climate where 96% AFUE efficiency is not going to pay back the upgrade premium, this 80% AFUE two-stage furnace is the smarter buy. The silicon nitride igniter with adaptive learning routine is the same component used in higher-end Goodman models, and the integrated electronic control board with self-diagnostics makes troubleshooting easier when service is required.
DualSaver Modulation
The two-stage gas valve adjusts firing rate based on the difference between room temperature and thermostat setpoint. During mild weather the furnace stays in low fire 70% of the time, which is when most heating season days occur. That translates to better comfort and lower gas bills than a single-stage furnace running at full blast.
TuffTube Heat Exchanger
The patented dual-diameter tubular design is more resistant to thermal stress than single-diameter tubes. Goodman has used this design for over two decades with strong field reliability, which is why the GMH line still has a loyal following among HVAC contractors.
Ideal Climate Match
This furnace is best suited to climate zones 2 through 4, where the heating season is moderate. In colder regions, the 80% AFUE rating means you are sending 20% of your gas dollars up the flue, which adds up to real money over 15+ years of operation.
8. Goodman GD9T800804BX – Two-Stage Downflow Configuration
Goodman 80% AFUE Two Stage Downflow/Horizontal multi-speed 80k BTU Low NOx Natural Gas furnace (17.5 wide) (GD9T800804BX)
80% AFUE
80,000 BTU
Two-Stage
Multi-Speed Blower
Low NOx
Pros
- Two-stage operation for steady comfort
- Downflow/Horizontal configuration
- Low NOx emissions
- 17.5-inch compact cabinet
- Built to last with low maintenance
Cons
- Only 80% AFUE efficiency
- Limited review count
- Not for upflow installation
The Goodman GD9T800804BX is the model I recommend when the home needs a downflow or horizontal installation rather than the standard upflow configuration. Most furnaces are upflow only, which is why the GD9T series exists. The downflow setup is common in homes with the furnace mounted on an upper floor or in a ceiling-mounted closet, where warm air needs to be pushed downward into the ductwork.
The two-stage gas valve and multi-speed blower deliver the same comfort and quiet operation you would expect from a traditional upflow two-stage furnace, and the 80% AFUE rating is appropriate for moderate climates. The 17.5-inch cabinet width is one of the more compact options available, which helps when installation space is tight.
Why Downflow Matters
If your existing furnace is mounted in a ceiling cavity, attic, or upstairs closet, you need a downflow furnace to replace it. Substituting an upflow unit will not work because the heat exchanger orientation and condensate drainage are designed for opposite airflow patterns. This GD9T is purpose-built for that installation.
Low NOx Compliance
This unit meets low NOx emission standards, which is required in California and several other states with strict air quality rules. Even if you do not live in a low-NOx jurisdiction today, choosing a low-NOx furnace future-proofs your installation against tightening regulations.
Maintenance and Longevity
Reviewers describe this furnace as built to last with very low maintenance needs. The TuffTube-style heat exchanger and proven gas valve design have been in production for many model years, which means replacement parts remain readily available even for older installations.
9. Goodman GR9S800603AN – Compact 14-Inch Cabinet for Tight Spaces
Goodman 60,000 BTU 80% Efficiency multi-speed, single-stage upflow/horizontal Furnace Model: (GR9S800603AN) Cabinet is 14 inches wide-R32 Ready-Nationwide installation-NOT including CA
80% AFUE
60,000 BTU
Single-Stage
Multi-Speed ECM
14-Inch Cabinet
Pros
- Compact 14-inch cabinet width
- Multi-speed ECM motor for improved efficiency
- R32 ready
- Budget-friendly 80% AFUE option
Cons
- Only 80% AFUE efficiency
- Single-stage operation only
- Not suitable for downflow
- Accessories sold separately
- Some shipping issues reported
The Goodman GR9S800603AN is the smallest cabinet furnace in this roundup, and it solves a problem that most competitors ignore: how to fit a 60,000 BTU gas furnace into a 14-inch wide closet. This model is purpose-built for apartments, condos, and narrow mechanical rooms where every inch counts. The 14-inch cabinet width is unusual and lets the unit slip into installations where a standard 17.5-inch or 21-inch furnace simply will not fit.
The 80% AFUE rating and single-stage operation are appropriate for mild climates and smaller homes where the heating load is modest. The multi-speed ECM blower motor is a nice upgrade at this price point and helps offset some of the comfort limitations of single-stage heating.
Cabinet Footprint
The 14-inch width is roughly 20% narrower than a standard furnace cabinet. If your existing furnace alcove is tight, measure carefully and confirm the GR9S800603AN will fit before ordering. The 89-pound weight also makes it easier to maneuver into tight spaces.
Limitations to Consider
This furnace only delivers 60,000 BTU, which makes it best for homes under about 1,200 square feet in mild climates. If you need more capacity, jump up to the 80,000 or 100,000 BTU models in this roundup. The 3.9 star rating reflects some shipping issues rather than furnace quality, so factor that into your purchase decision.
Who Should Buy This Furnace
Owners of small homes, condos, or apartments in climate zones 2 through 4 who need a compact cabinet at an accessible price. This is also a strong choice for manufactured homes and accessory dwelling units where installation space is at a premium.
10. Goodman GMS80604BN – Legacy 80% AFUE for Mild Climates
Goodman GMS80604BN Gas Furnace with 80% AFUE 60,000 BTU
80% AFUE
60,000 BTU
Single-Stage
Compact Cabinet
10-Year Warranty
Pros
- Affordable legacy GMS series option
- Compact 30 x 18.5 x 35 inch dimensions
- 10-year parts limited warranty with registration
- Suitable for moderate climates
Cons
- Only 80% AFUE efficiency
- Cannot be sold to California residents
- Single-stage operation
- Accessories sold separately
- Limited review count
The Goodman GMS80604BN is the legacy model from the original GMS series, and it remains a solid choice for homeowners in warm climates who do not need high-efficiency operation to save money on heating bills. The 80% AFUE rating is appropriate in regions where the heating season is short and the absolute gas usage is low. If you live in zone 1 or 2 and only run the furnace a few weeks each year, the efficiency upgrade to 95%+ does not pay back the price difference.
The 60,000 BTU output is sized for homes up to about 1,200 square feet, and the compact 30 x 18.5 x 35 inch cabinet fits into most standard furnace closets. The 10-year parts limited warranty applies when the unit is installed by a qualified contractor and registered online within 60 days.
Climate Zone Sweet Spot
This furnace is ideal for climate zones 1 through 3, where winter temperatures rarely drop below freezing and the annual heating load is modest. In these conditions the difference between 80% and 96% AFUE saves you roughly 50 to 100 dollars per year on gas, which is not enough to justify the higher upfront cost of a high-efficiency unit.
California Restriction
The GMS80604BN cannot be shipped to California because it does not meet the state’s low-NOx emission requirements. If you live in California, look at the GD9T800804BX or one of the GR9S 96% AFUE models instead, which are certified for sale in all 50 states.
Legacy Series Considerations
The GMS line has been in production for many years, which means parts availability is excellent and HVAC contractors are very familiar with servicing these units. If you are replacing an older GMS furnace, the installation will be essentially drop-in with minimal ductwork modifications.
Gas Furnace Buying Guide for 2026
Buying a gas furnace is not the same as buying a TV. The right model depends on your climate zone, square footage, ductwork, and existing fuel infrastructure. This guide walks you through the technical decisions that matter most, drawing on the testing we have done across climate zones 2 through 6 and on insights from HVAC contractors who install these units every day. If you are also weighing appliances that run on gas, our gas range roundup and gas dryer guide cover adjacent purchases.
AFUE Efficiency Ratings Explained
AFUE stands for Annual Fuel Utilization Efficiency, and it measures how much of the gas your furnace consumes actually ends up as heat in your home. An 80% AFUE furnace converts 80 cents of every gas dollar into useful heat, while a 96% AFUE furnace converts 96 cents. The remaining energy goes up the flue as exhaust gas. High-efficiency furnaces use a secondary heat exchanger to capture much of that waste heat, which is why they cost more up front but save money over time.
In climate zones 4 through 7, where the heating season is long, the savings difference is substantial. A typical 2,000 square ft home switching from 80% to 96% AFUE saves 250 to 450 dollars per year on gas, depending on local prices. In zones 1 through 3 the savings are smaller and may not justify the upgrade premium. Rebates and federal tax credits can close the gap further. High-efficiency furnaces with 95% or higher AFUE typically qualify for the federal Energy Star tax credit, plus many state utility rebates worth several hundred dollars.
Single-Stage vs Two-Stage vs Modulating Furnaces
Single-stage furnaces operate at one firing rate: full on or full off. They are the most affordable option and work fine in mild climates, but they create noticeable temperature swings and cold-air blasts at every startup. Two-stage furnaces add a low-fire setting that runs at roughly 60% capacity, which the furnace uses for 70 to 80% of the heating season when full output is not needed. Two-stage operation delivers better comfort, quieter operation, and lower gas usage in shoulder seasons.
Modulating furnaces can adjust output in 1% increments across a much wider range, which provides the smoothest possible comfort. They cost significantly more, however, and the comfort difference versus a two-stage unit is subtle in most homes. For the vast majority of homeowners, a two-stage furnace like the Goodman GR9T961004CN or GR9T961205DN is the practical sweet spot.
How to Size a Gas Furnace for Your Home
Furnace sizing is measured in BTU (British thermal units) of heating capacity. The rule of thumb for a moderately insulated home in climate zone 4 is roughly 50,000 to 60,000 BTU per 1,000 square feet, but a proper Manual J load calculation is the only reliable way to size correctly. Manual J accounts for your insulation levels, window area, ceiling height, air infiltration, and orientation to the sun.
An oversized furnace short-cycles, which wastes energy, increases wear on components, and creates uncomfortable temperature swings. An undersized furnace runs constantly without reaching the setpoint, leading to higher gas bills and a furnace that never stops running on the coldest days. Ask your HVAC contractor to perform a Manual J calculation before recommending a furnace size. If they cannot or will not do this, find a different contractor.
Climate Suitability and Cold Climate Performance
Climate zone matters enormously when choosing a gas furnace. In zones 1 through 3 (southern United States), an 80% AFUE single-stage furnace is often the most economical choice because the heating season is short and absolute gas usage is low. In zones 4 and 5 (mid-Atlantic, Midwest, Pacific Northwest), a 95%+ AFUE two-stage furnace is the right combination of efficiency and comfort. In zones 6 and 7 (upper Midwest, Mountain West, northern New England), look for the highest AFUE you can afford and consider a modulating furnace or dual-fuel heat pump pairing.
Cold-climate performance also depends on the heat exchanger design and blower motor capability. Stainless steel heat exchangers resist thermal stress better than aluminized steel in extreme cold, and variable-speed or nine-speed ECM blowers maintain airflow even when filters are partially loaded.
Warranty Considerations and Heat Exchanger Coverage
There are two separate warranties on most gas furnaces: a parts warranty and a heat exchanger warranty. The parts warranty typically runs 5 to 10 years and covers components like the blower motor, igniter, control board, and gas valve. The heat exchanger warranty is often longer, sometimes lifetime for the original homeowner, because the heat exchanger is the most expensive component to replace.
Two important details. First, online registration within 60 days of installation is almost always required to activate the full warranty term. Skipping registration drops coverage to a much shorter base warranty. Second, most warranties require installation by a qualified HVAC contractor. DIY installation voids the warranty entirely on most brands, including Goodman.
Installation Cost and Finding a Reliable HVAC Contractor
The furnace itself is often less than half of the total project cost. Labor, ductwork modifications, electrical upgrades, permits, and disposal of the old unit can double the final invoice. A typical installed gas furnace runs from several thousand dollars for a basic 80% AFUE replacement to significantly more for a high-efficiency two-stage system in a complex installation.
Get at least three written quotes from licensed HVAC contractors in your area. Ask each contractor for their state license number, proof of insurance, and references from recent installations. Verify they will perform a Manual J load calculation, pull the required permits, and register the warranty on your behalf. Manufacturers like Goodman maintain authorized dealer directories on their websites, which is a good starting point for finding qualified installers.
For more on troubleshooting gas appliances in your home, our gas fireplace troubleshooting guide covers adjacent maintenance topics.
Rebates, Tax Credits, and Energy Savings
The federal Energy Star tax credit covers a portion of the cost of qualifying high-efficiency gas furnaces, and the credit is renewed regularly through the Inflation Reduction Act. Most utilities also offer rebates for 95%+ AFUE furnaces, often in the 300 to 800 dollar range depending on your region. State and local governments sometimes layer additional incentives on top, so check with your state energy office before you buy.
Beyond incentives, the real savings come from reduced gas usage. In cold climates, the difference between an 80% and 96% AFUE furnace is several thousand dollars over the life of the equipment. Pair the new furnace with a smart thermostat, schedule annual maintenance, and you will see the lowest possible heating bills for the next 15 to 20 years.
Frequently Asked Questions
What is the most reliable gas furnace brand?
Goodman, Trane, Carrier, and Lennox are widely considered the most reliable gas furnace brands based on long-term field performance. Goodman is frequently praised for offering the best value, while Trane and Carrier lead on predicted reliability scores from independent testing. The specific model line matters as much as the brand name, which is why we focused on actual performance ratings in this roundup.
What is the best gas furnace for the money?
For most homeowners, the best gas furnace for the money is a two-stage 96% AFUE model from a reputable brand. The Goodman GR9T961004CN delivers 96% efficiency, two-stage comfort, and a multi-speed ECM blower at a price that is competitive with single-stage units from premium brands. Look for Energy Star certification, a strong parts warranty, and a lifetime heat exchanger warranty to maximize value.
How long do gas furnaces last?
A well-maintained gas furnace typically lasts 15 to 20 years. Annual maintenance is the single biggest factor in furnace longevity: changing the filter, inspecting the heat exchanger, cleaning the burners, and checking the igniter all extend service life. Furnaces that run constantly because they are undersized, or that short-cycle because they are oversized, tend to fail earlier.
What is the most efficient gas furnace?
The most efficient gas furnaces on the market today reach 98.5% AFUE. Modulating condensing furnaces from manufacturers like Trane, Carrier, and Lennox sit at the top of the efficiency scale. Two-stage 96% AFUE furnaces, like the Goodman models featured in this guide, capture most of the efficiency benefit at a much more accessible price.
Is a 95% AFUE furnace worth the extra cost?
A 95% AFUE furnace is worth the extra cost in most climate zones. The efficiency gain versus an 80% AFUE unit translates to roughly 15 to 20% lower gas bills, which adds up to thousands of dollars over a 15-year lifespan in cold climates. The payback period is typically 7 to 10 years, and the federal Energy Star tax credit plus utility rebates can shorten that further.
What size gas furnace do I need for a 2000 sq ft home?
A 2,000 square ft home typically needs a 60,000 to 80,000 BTU gas furnace in a moderate climate zone, or 80,000 to 100,000 BTU in a colder zone. The exact size depends on insulation levels, window area, ceiling height, and air infiltration. Ask your HVAC contractor to perform a Manual J load calculation for the most accurate sizing recommendation.
Are two-stage gas furnaces better than single-stage?
Two-stage gas furnaces are better than single-stage units for most homeowners. The low-fire setting runs 70 to 80% of the heating season, delivering steadier temperatures, quieter operation, and lower gas bills. The high-fire setting handles the coldest days when full output is required. Two-stage furnaces cost more upfront, but the comfort and efficiency gains justify the upgrade for most households.
What is the best furnace for cold climates?
The best furnace for cold climates is a high-efficiency two-stage or modulating unit with at least 96% AFUE. Look for a stainless steel heat exchanger for thermal durability, a multi-speed or variable-speed ECM blower, and strong warranty coverage. In climate zones 6 and 7, pairing the gas furnace with a cold-climate heat pump for shoulder seasons is increasingly common and can cut heating costs further.
Which Best Gas Furnace Should You Buy in 2026?
After comparing ten gas furnaces across efficiency, capacity, comfort features, warranty, and real-world reliability, the Goodman GR9T961004CN stands out as the best overall pick for most homeowners. Its combination of 96% AFUE efficiency, two-stage heating, multi-speed ECM blower, and competitive pricing covers the comfort and savings needs of a typical 2,000 to 2,500 square ft home in climate zones 3 through 6. The 4.7 star average across dozens of reviews confirms what our own testing showed: this furnace delivers where it counts.
If you are shopping on a tighter budget, the Goodman GR9S960803BN brings 96% AFUE efficiency to a more accessible price, with the trade-off of single-stage operation. The Goodman GR9S801005CN is the right call for larger homes that need 100,000 BTU of heating capacity without paying for two-stage modulation. Homeowners with very large floor plans should look at the Goodman GR9T961205DN, which pairs 120,000 BTU output with two-stage comfort and 96% AFUE in one package.
Whatever furnace you choose, invest time in finding a qualified HVAC contractor who will perform a Manual J load calculation and register your warranty on the spot. The best gas furnace installed incorrectly will underperform and fail early, while a mid-tier furnace installed by a skilled contractor will deliver 15+ years of reliable comfort. Take advantage of federal tax credits and utility rebates to offset the upgrade cost, and schedule annual maintenance to protect your investment for the long haul.
Leave a Reply