When you no longer can tolerate your soaring energy bills and is desperate to cut down your energy bill you either would have to repair your furnace or replace it. An inefficient furnace will make things tough for you as it will increase your energy bill. If the furnace is more than 15 years old then it is wise to replace it with a new one. Such furnace also works making a lot of noise which will even effect the otherwise peaceful surrounding. So under such circumstances instead of going for repair it is smarter to go for a replacement. Heating expenses form a considerable part of your energy bill so you need to try reducing the heating cost in whatever ways you can. The heating units that are now available are energy efficient hence can save you a lot of money especially in the long run. So instead of spending on repair charges and energy bills replace the old unit with a new one.
Check the AFUE rating which is the Annual Fuel Utilization Efficiency when purchasing a new furnace. The best AFUE rating will mean that the furnace has got higher energy efficiency. A conventional furnace has got the least AFUE rating hence the heating cost of a conventional furnace is very high compared to high and mid efficiency furnaces. A high efficiency furnace is not only going to save you money in the long run but is also the most environmental friendly furnace as lesser energy is used in such furnaces thus avoiding energy wastage.