basics on efficient new furnaces
Top manufacturers are claiming that new furnaces provide $500-$1000 dollars each year in savings, compared to standard furnaces. In fact, the AFUE (Annual Fuel Utilization Efficiency) of new furnaces has increased from levels of 60-70%, two decades ago, to levels of 90-95% or even to 98% (in the case of premium gas furnaces), making it possible to reduce heating bills by 20% or more.
New Homes
Furnaces are the commonest residential heating system in the North America, but there are alternatives to them, namely if your are building a new home. See: Furnace Alternatives
Ducted Central Furnaces and ductless...
Furnaces are typically central heating systems, with ducts distributing the heat to the several rooms. But furnaces can also be ductless. Besides traditional ducted furnace systems, there are now ductless direct vent furnaces - a new and interesting technological option for smaller needs or well insulated homes.
Modern ductless wall gas furnaces are in direct competition with gas stoves or gas fireplace inserts.
Selecting a furnace
The overall efficiency of a furnace (or a boiler) is given by its Annual Fuel Utilization Efficiency (AFUE) coefficient, while its capacity is given in BTU (British Thermal Units).
The Energy Star furnace rating is based on its AFUE, but the quality of a furnace can also be attested by certifications like those of UL or Gas Appliance Manufacturers Association.
New Furnace features
New regulations are squeezing inefficient furnace systems out of market, making the offer of the several manufacturers very similar in their performance, increasing the importance of some specific furnace features. See, for more information: Furnace features.
New Condensing and Multi-Stage Furnaces
Two, three and multi-stage furnaces are at the top of the new furnace technology. They have an efficiency (AFUE) above 89-90% (condensing furnaces). They are able to recapture most of the water vapor and gases wasted in traditional systems, condensing them and producing extra-heat.
Two, three and multi-stage furnaces offer a sophisticated capacity to reduce temperature swings and to improve comfort. But they are also more expensive, raising the question: do they worth their price? And which are the differences between them?
See, for details: Multistage, Three, Two and Single-stage furnaces
New furnaces and prices
A conventional gas or oil furnace with a 85-90% AFUE (a mid-efficient unit) may cost you about $900-$1000 ($3,000 installed) while new 95% multi-stage furnaces may cost you up to $3,500-$4,000 installed…
See, for details: New Furnaces Prices
Furnaces and home insulation
The size of a furnace depends a lot on the insulation levels of your home. High insulated homes require smaller furnace systems. So, if a big improvement of your home's insulation is on your short terms goals, perhaps it's a good idea to postpone the buying of the furnace to that later moment. Otherwise, you are running the risk of buying an oversized furnace.
See, for more information:
Furnace sizing tips
Home insulation basics.
High, mid and low efficient Furnaces
New furnaces are forced-air systems, that is, they rely on a blower system to deliver the hot air through the house. Gravity furnaces - using natural convection - are outdated. But the big news in what concerns the furnace technology are high-efficient multi-stage furnaces...
See:
Low, Mid and High Efficient Furnaces
Electric, wood Pellet, oil and New gas furnaces
New furnaces can run on gas, oil, wood pellets and other biomass materials... Gas is by far the most popular choice. As to new electric furnaces, they are in fact air source heat pumps, a heating and cooling solution for non-freezing climates.
See also:
Furnace Types
Furnace Performance and Rating
Gas vs. Oil furnaces
Direct-Vent Ductless Gas Furnaces
Wood Pellet Furnaces
Installation and Maintenance of New Furnaces
An high-efficient furnace from a top manufacturer can be outperformed by a furnace with a lower efficiency if the installation isn't up to its efficiency (see Top Furnace Manufacturers).
Regular maintenance is also very important, and involves more than just replacing the furnace filters. Similarly, professional maintenance - once a year for oil furnaces and every 2-4 years for gas furnaces - is crucial to avoid safety hazards and to get energy savings. See: Furnace Care
See also:
The Best of Furnaces
Furnace Tax Credits and Rebates