A central-heating system can become expensive if not properly maintained, and a poorly maintained one can become dangerous. If you spend $250 (or more) per month on your heating bill you could be wasting as much as $600 per year, if you have not properly maintained your central-heating system. And it doesn't make any difference what type of central furnace you have. Even a simple window-mount heat pump can be damaged beyond repair if not regularly cleaned. The coils can become clogged with dust and debris and the system can rapidly fail.

Central systems that have heat exchangers can become whole-house gas chambers filling every room with undetectable, poisonous carbon monoxide gas. Don't begin using your central furnace this winter until you have had your heat exchanger checked by a bonafide heating contractor. While he's there, ask him to replace the filters, and check the fan belt and oil.

Although we don't recommend that you attempt to check your heat exchanger, we do feel it is safe for you to check the condition of your blower-fan drive-belt. A worn or frayed fan belt isn't dangerous, but it can increase your electric bill unnecessarily. If the belt isn't tight enough it will allow the drive motor to turn extra revolutions for each rotation of the fan. Each time the drive motor turns without rotating the fan, money comes out of your pocket. Be careful though. If the belt adjustment is too tight, it can damage motor and fan bearings, and both are expensive items to repair. A frayed fan belt should be replaced even if the tension adjustment is correct. When the fan belt becomes frayed it soon will split - possibly after dark on the year's coldest evening when all the stores are closed. It's a good idea to have an extra one on hand. Drive a nail in the wall next to the furnace. Wrap the extra fan belt in an old towel or rag (to keep it clean) and then hang it all on the nail.

System lubrication is a task that just about anyone can perform. Proper lubrication will cause quieter operation and will increase bearing life. Best of all, the free, smooth-running bearing operation that results will reduce stress on the drive motor, and will ensure cheaper motor operation. Although there is no such thing as too much lubrication, excess lubricant can be thrown off the bearings and onto the interior of the furnace - and oil is a dust collection surface. So, be careful.

The burners also are important. They heat the exchanger, which warms the air that is blown through the ducts and blown out the registers that heat the home. Therefore, the burners have a great deal to do with the operating efficiency of the system. Make an investigation of the burners to ensure that the flames burn blue. An orange flame indicates that the fuel is not burning clean and hot. Often the burners corrode or rust, and the flame ports become clogged resulting in reduced efficiency.

The filters in your furnace probably are made from hemp, fiberglass or nylon and are bound in a cardboard frame. If this is the case, chances are your filters are the disposable type. We purchase ours by the case and replace our filters monthly. In addition, electronic filter units can be built in to your central furnace system. Although they are expensive, they can be cleaned and will outlast two or three furnace replacements. With these systems, maximum filtration is achieved. To properly maintain an electronic system, remove the filter drawer, hose it down in the garden, let it dry and slip it back into place. This type of filter should be cleaned two to four times a year depending on frequency of use and conditions where you live.

In many instances your local public utility will offer free inspection services and make maintenance recommendations.