American households spend on average $638 on heating per year (EIA). That value increases significantly in colder climates, where annual heating bills of $1.000 and more are common. Heating is, typically, the highest energy cost for most families.
So, consider carefully your heating system... If you are building a new home or planning a big renovation, consider possible alternatives to central furnaces, by using very high levels of air sealing and insulation.
Efficiency (measured by the AFUE coefficient of the furnace) has a lot to do with the price of a furnace for central heating. But the installation and upgrades in the ducts and venting system may cost a lot more than on the price of the equipment.
- 80% AFUE gas furnace (installed):
»» $2,500 to $9.000
- 90% AFUE gas furnace (installed):
»» $3,500 to $10.000
- 80% AFUE new oil furnace (installed):
»» $1.500 to $5.000
- 95% multi-stage gas furnace (installed):
»» $4.500 to $11.000
- Wall gas furnaces:
»» $1.500 installed
- 90% top pellet boiler/furnace (installed):
»» $5.000 - $6.000 minimum
The main function of furnaces is not so much to heat the house, but to replace the heat that is lost through air leaks and the walls and ceilings. And if you reduce dramatically those losses through high levels of insulation and air sealing, you can install a different and more inexpensive heating system, with much lower running costs (see, on these issues: Insulation for low-energy homes and New Homes Guide).
Avoid Low-efficient furnaces and Cost-savings in the ducts and venting
When buying a new furnace, do not fall in the temptation of trying to save yourself some money by selecting low-efficient furnaces, or by not implementing key improvements in your ducts and venting system. You may save thousands of dollars in the short run, but you will spend many more thousands during the lifetime of the furnace.
You should not forget the energy loss associated to low or even mid-efficient furnaces, and to leaky and undersized ducts, or to venting systems, and that furnaces are expected to last 20 years or more (see table above).
Heat losses amounting to 40% of the heat delivered by the furnace are common in homes with leaky and un-insulated ducts and poor venting systems.
In other words: you can achieve energy savings of 40% or more by choosing an energy efficient furnace (a 90%+ furnace) and by investing in your ductwork, venting and distribution system (and in your home’s sealing and insulation).
Small differences in the AFUE May Not be Relevant
Improvements in the insulation and sealing of the house and in the ductwork and venting system of the furnace are crucial for very high energy savings.
The most important - when installing a new system - is not small differences in the AFUE (energy coefficient) of the furnace. The most important is the type of furnace (a 90%+ multi-stage and variable speed furnace) and improvements in the ductwork, and venting.
It’s these last factors that can provide higher energy savings. Modifications in the ducts and venting system should not be postponed by short-term cost-saving goals. They will end up by being highly costly.
The prices of the furnaces and the payback of the investment
It’s very difficult to have an accurate estimation of the installed prices of furnaces and their paybacks. They vary with the brand and the AFUE and type of furnace, but most of all with the installation costs.
The installation can double or triple the cost of the furnace; replacing a ductwork, or re-lining and changing the chimney and venting system can be more expensive than the furnace itself.
The prices listed at the beginning of this page are just general price ranges based on estimates from a top brand.
That’s a too wide range, rather inconclusive, except in what concerns the impact of the installation costs.
The efficiency (AFUE) of the furnace may increase the cost of the system by $1.000-$3.000, but rarely more.