- What Is The Highest Efficiency Furnace
- High Efficiency Furnace Buying Guide
- High Efficiency Gas/Propane Furnace List & Reviews
- High Efficiency Oil Furnace List & Reviews
- A Final Word on Furnace Cost
What Is The Highest Efficiency Furnace
There are different lists for gas and oil, and we’ve got them both.
The highest efficiency furnaces are:
- Lennox SLP98V Gas Furnace
- Carrier Infinity 98 Gas Furnace
- Bryant Evolution 987M Gas Furnace
- Heil Ion 98 Gas Furnace
- Heil QuietComfort Deluxe 98 Gas Furnace
- Goodman GMVM97
- Ruud U98V Gas Furnace
- York YP9C Gas Furnace
That list is gas/propane furnaces.
The highest efficiency oil furnaces are:
- Adams AHEO Highboy Condensing Oil Furnace
- Lennox Signature Series SLO185V Oil Furnace
- Carrier Performance 80 OVL Oil Furnace
High Efficiency Furnace Buying Guide
If you want more than just their names, we’ve got reviews and more.
This High Efficient Furnace Reviews below includes details about each model on the list – how they compare to one another with an approximate cost for each.
If you’re just starting your research on furnaces, our Gas Furnace Reviews and Buying Guide might be of interest. It has complete buying information that will help you select a really good furnace fit for your purposes.
For example, an 80% efficient furnace is a better choice in San Diego and similarly mild climates than it is in Minneapolis, even though it is far less efficient than a 98% furnace. Why?
Because in San Diego it would take the life of the furnace to recoup the higher cost of the super-efficient model through lower energy bills. In fact, you’d likely never make the extra money back. And that doesn’t consider the time value of money invested.
That’s just one of the kinds of scenarios we think through in our comprehensive Furnace Buying Guide.
High Efficiency Gas/Propane Furnaces
Before getting to the reviews, here is an explanation of how variable heating compares with single-stage and two-stage heating.
Variable capacity heating is like cruise control for your furnace.
If you use cruise control in your car or truck, then you understand this concept. You set the speed for 60, and the motor will work as hard as necessary to keep you going 60 miles per hour. You’ll feel it work harder on hills and then back off when back on level road.
Most furnaces are single-stage or two-stage models. That equates to a vehicle engine that can only work at one or two levels.
Understanding how single-stage and two-stage furnaces work will help make sense of variable heating furnaces.
- Single-stage Heating
When the thermostat triggers the furnace, it comes on full force, 100%. When the thermostat is satisfied, the burner shuts off, and the blower keeps pushing air through the ducts for up to a minute to distribute the hot air still in the system.
Heating efficiency: These furnaces are made in 80% efficient models and 90+ models. The most efficient single-stage furnace is about 96%.
- Two-stage Heating
These furnaces have heat output of 65% (or 70% depending on model) and 100% of capacity. They run at the lower capacity to maintain heat and at full capacity to boost heating, like when you walk into a cold house and crank up the heat by 10 degrees.
Heating efficiency: This is like pushing the gas pedal 2/3s of the way down for level driving and all the way down to get up a hill. Then you would shut it off and let it coast until you had to turn it on again and give it gas to get somewhere. 65%/100%/Off heating is more efficient than single-stage heating. But there’s a more efficient way.
- Variable Capacity Heating
Instead of the gas valve running at one or two capacities, it modulates up and down in increments of 1% or less depending on the model. The range is 40% to 100% for most variable capacity furnaces.
They run at the lowest capacity needed to keep the temperature where you want it. Cycles are longer, quieter and more even.
These high-cost, premium-performance furnaces also have variable-speed blowers. The speed of the blower matches the heating level to optimize indoor comfort.
Heating efficiency: This is like super-smooth cruise control. The furnace uses just enough gas to maintain temperatures that vary in your home by less than 1%. This also produces the most efficient heating. Variable capacity furnaces range in efficiency from about 96% to almost 99%.
Return on Investment
From a strictly financial perspective, paying more for variable capacity heating is not a good investment. As you can see, you’ll gain just a few percentage points in efficiency.
Here are average costs for 100,000 BTU furnaces:
- Single-stage 92% furnace: $1,250
- Two-stage 95% furnace: $1,800
- Variable capacity 97.5% furnace: $2,650
You can do the math based on your average winter heating bills. How much will you save if you have a furnace that is 97.5% efficient vs. 95% or 92% efficient? The average homeowner in a cold climate would save $20-$44 per year based on $800 per year for heating. You can see that you’d never recoup the $850 to $1,400 spent for the most efficient furnace.
Reason to Consider a Super-efficient Furnace
It isn’t cost savings, as we’ve seen.
It is indoor climate comfort.
- Heating balance: The variable-capacity gas valve creates quiet, balanced heating that keeps your home at precisely the temperature you want.
- Comfortable air: The variable-speed blower (also available on some two-stage furnaces) prevents blasts of cool air at the beginning and end of a cycle.
- Better AC performance: The blower also creates better dehumidification when the furnace is acting as the air handler for central air conditioning.
A few homeowners buy the most efficient furnace they can because of their commitment to ecofriendly heating. We support that reason too. But the most common reason is climate control.
Get Estimates on Each Type
If a salesperson is pushing a variable capacity furnace, ask the person to write up estimates for single-stage and two-stage furnaces with comparable efficiency – within 3% to 6%, as in our example.
Then do your own math on energy savings.
What is the difference between a natural gas furnace and a propane furnace?
The gas valve. That’s all. Natural gas and propane have different pressure ratings, so must be dispersed into the furnace burner at different rates in order to burn safely and efficiently.
Any natural gas (NG) furnace can be converted to burn propane (LP for liquid propane) by changing the gas valve to one designed for propane. A propane to natural gas conversion is possible too.
Almost all gas furnaces come from the factory equipped to burn natural gas.
However, all furnaces can burn propane. A few furnaces are shipped with a propane gas valve, especially to wholesalers in areas where propane is prominent. Otherwise, the gas valve is changed during furnace installation. It’s a simple switch.
High Efficiency Gas/Propane Furnace List & Reviews
There is little distinction between these furnaces in terms of efficiency, performance or warranty.
- They all have variable capacity gas valves, variable speed blowers and condensing technology that uses a secondary heat exchanger to transfer more heat from combustion gases.
- The heat exchangers have a lifetime warranty.
- We list the general parts warranty and warranty perks. Warranty perks vary and are worth considering.
- Quality ratings are 1 (poor) to 5 (excellent)
- Costs are averages across the country. As we noted, local dealers have wide sway in pricing. Also, each furnace is made in various sizes from 40K or 60K to more than 120K BTUS.
It’s time to compare and contrast the most efficient furnaces with your other options.
#1 Lennox SLP98V
This is currently the most efficient gas furnace available. Lennox leads the industry in efficiency. It makes the most efficient heat pump and air conditioner too.
Only 1.3% of the heat created by this furnace is lost out the vent. The rest is usable heat for your home. That is remarkable efficiency.
Warranty features: 10 years on parts. No perks.
Quality rating: 3.75 Lennox uses the most proprietary parts of any leading brand. And some of those parts aren’t as good as third-party parts made by Copeland, Emerson and other respected parts manufacturers. Also, due to using their own parts, there can be parts delays of a few days to more than a week.
Installed cost: $3,250-$5,500
#2 Carrier Infinity 98 59MN7
Carrier was an early adopter of variable capacity performance in heat pumps and gas furnaces. They call the technology Greenspeed to reflect the ecological benefits of the outstanding efficiency.
This unit can be used in a dual fuel system with a heat pump. Carrier calls it Hybrid Heat. The heat pump does the heating when temperatures are above freezing. The furnace heats in colder weather. The system transitions seamlessly between the two components. In climates that do not experience (much) freezing weather, a heat pump alone is the most efficient way to heat your home. See our comprehensive Heat Pump Buying Guide for all the details.
Warranty features: 10 years. No perks.
Quality rating: 4.5 Carrier’s best lines, Infinity and Performance Series are very solid furnaces with very good track records for reliability.
Installed cost: $3,000-$5,300 for furnaces from 60K to 120K BTU.
#3 Bryant Evolution 987M
Bryant and Carrier are made by United Technologies Corporation and are very similar. This Bryant gas furnace is slightly less efficient than the Carrier Infinity above.
Warranty features: 10 years. No perks (hang on, they’re coming).
Quality rating: 4.5 Bryant’s furnaces are very dependable.
Installed cost: $2,900-$4,750 for units from 60K to 120K BTUs.
#4 Heil Ion G97CMN & QuietComfort Deluxe 98
These are very similar furnaces. The Ion is new for 2020. Both can be controlled by the new Heil Ion thermostat with WiFi capability.
Furnace Fact! Heil is owned by ICP/International Comfort Products, and ICP is owned by Carrier/UTC. These units are similar in many ways to Carrier and Bryant.
In addition, ICP makes identical furnaces to Heil under brand names Day & Night, KeepRite, Arcoaire, ComfortMaker and Tempstar. If you can’t find a Heil dealer where you live, you should be able to locate the same furnace from one of these other brands. Only the name will be different.
Warranty features: 10 years on parts. Plus, if the heat exchanger fails in the first 10 years, Heil (or other ICP brand) will replace the entire furnace.
Quality rating: 4.25 ICP makes reliable furnaces and they cost less than comparable Carrier and Bryant models. This makes Heil and other ICP brands an excellent value for the money.
Installed cost: $2,650-$4,300 for models from 60K to 120K BTUs.,
#5 Goodman GMVM97
Goodman is overcoming its reputation as a budget brand. It still makes affordable furnaces and other HVAC components, but the quality is better, the prices are little higher and the warranties not quite as good.
Furnace Fact! Daikin and Amana furnaces are identical to Goodman. Daikin Global owns all the brands. This unit is available as the Daikin DM97MC and the Amana AMVM97.
Warranty features: 10-year parts warranty and a 10-year replacement warranty if the heat exchanger fails in that time.
Quality rating: 4.0 Good, but not one of the very best.
Installed cost: $2,500-$4,000
#6 Rheem Prestige R98V
Rheem made its first variable capacity furnaces a few years ago, and this is the best and most efficient. This is a WiFi furnace when you buy the Rheem EcoNet WiFi thermostat or a WiFi-capable brand like Lux or ecobee.
Furnace Fact! Ruud and Rheem are identical brands. The Ruud EcoNet Ultra U98V is the same furnace by a different name.
Warranty features: 10 years on parts. The furnace comes with a Lifetime unit replacement warranty if the heat exchanger fails. Rheem and Ruud are the only brands to offer this protection now that Goodman no longer does.
Quality rating: 4.0 Paloma Industries, the owner of Rheem and Ruud, has upgraded quality in the last five years after its brands got consistently low ratings.
Installed cost: $2,750-$4,200 for furnaces from 60K to 115K BTUs.
#7 Coleman Echelon CP9C
Like Rheem, Coleman’s quality had deteriorated and service records were not as good for a period of time. However, in recent years, upgrades to quality were made, and Coleman furnaces are more dependable.
Furnace fact! Coleman has sister brands too. In this case, York, Luxaire and Champion. The sister brands make furnaces identical to this, but with their own brand name.
Warranty features: 10 years on parts plus a 10-year replacement warranty on the heat exchanger. You’ll get a new furnace is the heat exchanger fails in the first decade. That’s also true if you buy this as a York, Luxaire or Champion.
Quality rating: 3.75
Installed cost: $2,650-$4,175 for models from 60K to 120K BTUs.
A Few More to Mention
You might be wondering where Trane is or a few other familiar brands.
We limited out a list to units with 98% efficiency or higher. Here are a few 97% furnaces. Identical furnaces are shown together.
- Trane XC95M & American Standard Platinum 95: 97.3%
- Aire Ease A97MV & Armstrong Air A97MV: 97%
High Efficiency Oil Furnace List & Reviews
The first unit in this list is super-efficient and very expensive. The second two are more affordable but not as efficient.
#1 Adams AHEO Highboy Condensing
Adams is widely considered the best manufacturer of oil furnaces in North America. You get what you pay for!
Furnace fact! This furnace uses condensing technology like the gas furnace models above. A secondary heat exchanger is used to transfer additional heat out of the exhaust gases. Most oil furnaces are not condensing furnaces.
Warranty features: N/A
Quality rating: 4.75
Installed cost: $7,500-$10,500 for units from 58K to 115K BTUs.
#2 Lennox Signature Series SLO185V
Lennox makes just two oil furnaces. This unit has a variable-speed blower for increased climate control and indoor comfort.
Warranty features: Lifetime heat exchanger and 10-year parts warranties.
Quality rating: 4.25 This is a dependable oil furnace that should last 18-25 years when maintained according to Lennox guidelines.
Installed cost: $4,850-$7,000 for units from 105K to 140K BTUs.
#3 Carrier Performance 80 OVL
Carrier and other leading HVAC brands make a limited number of oil furnaces for use mainly in the Northwestern United States.
This is a “lowboy” oil furnace meaning it has a low, squat profile with a larger footprint than a gas furnace.
Furnace fact! This furnace is available from several other brands – Bryant, Day & Night, Heil and others. They are all made by United Technologies Corporation (UTC).
Warranty features: Lifetime heat exchanger and 10-year parts warranties.
Quality rating: 4.25
Installed cost: $4,200-$7,500 for units from 77K to 154K BTUs.
A Final Word on Furnace Cost
The cost figures we gave in the example are averages among all brands. Each brand and each salesperson can shift numbers around to make one model appear more attractive than the others in the comparison. There is no such thing as hard-and-fast pricing in the furnace industry. That’s why comparing written estimates on models and from various dealers is crucial.
If you’d like to talk to local furnace installers about your options and their costs, use our Free Local Quotes for or call the 800 number. There is no cost and no obligation for getting these very competitive quotes.