There are many options for home heating but the most common is a central heating system driven by an energy efficient furnace. The furnace is most important part of any heating system. It provides both the heating and means of distribution for the heated medium, be it air, water or steam. The furnace is typically gas fired utilizing natural gas or propane, but there are also cases where electricity is used.

A furnace consists of a burner, a heat exchange system, and a blower or pump depending on the type of heat distribution system that is being utilized. A forced air furnace will directly heat the air pulled from inside the home and pass the air through a duct that passes over the burner. The heater air is then distributed using ductwork throughout the home. Exhaust gasses are normally vented using a stack that is routed to the outside of the home. A high efficiency furnace can capture this escaping heated air and re-use it providing very little wasted energy.

Furnaces that distribute heat using hot water or steam work in essentially the same way except the blower and heat exchanger carry fluid instead of air. This type of furnace transfers heat to a fluid bearing vessel called a boiler. The boiler is then connected to the heat distribution system that carries the heated water or steam to areas of the house. While it is more efficient to heat water than air, you should not be fooled by thinking this type of furnace is inherently more efficient that an standard forced air furnace. In the end both types of furnace heat the air.

When you are looking to buy a furnace, here are some important tips you should remember:

• First decide on the type of fuel and distribution system you will be using.
• With the help of a professional, decide on the size furnace you will need to heat your space.
• Consider the venting options for your furnace. This is important if you are relocating a system or changing the fuel type.
• Compare both the purchase price and operating costs. Cheaper furnaces can cost you much more in the long run. Remember, a furnace can last 20 to 30 years.
• Be sure you compare the warranties of any units you are considering. Make sure the manufacture will provide full replacement for at least the first year.
• Only consider furnace models that have been certified by a recognized laboratory or underwriter.