Winter brings chilly temperatures and the need for a well-heated home. Those who write the check for the monthly heating bill know why it's important for the furnace to be maintained and in peak operating condition. Overall, the most cost-efficient heating system is gas-fired central heat.

This takes into consideration installation and operating and maintenance costs. But even the best system must be properly maintained to operate at peak efficiency. Furnace maintenance involves cleaning, oiling and adjusting drive-belt tension. Ducting also should be clean and all connections should be solid and well sealed.

Caution: Before proceeding with any type of furnace maintenance make sure to shut off the gas and power to the unit.

Cleaning a furnace can be as simple as vacuuming. But, if rust buildup exists on the burners, they should be wire-brushed before vacuuming. Be careful not to bend or otherwise damage igniting wires and tubes that make up the pilot light system. Also, do not adjust air baffles unless you know exactly what you are doing. This adjustment determines the air-gas mixture for an optimum flame. If the flame in your furnace is orange, the baffles should be adjusted so that the flame burns blue. Many public utilities have a free service that will do this for you or will at least advise you if an adjustment is required. All interior areas of the furnace should be completely free of dust, debris, spider webs, and the like. A household vacuum cleaner is all that you will need.

The filter should also be clean. Paper filters should be replaced, not cleaned. Non-paper filters that can be cleaned should be washed with warm water and a mild detergent, air dried and returned to the system. It is important when the filter is replaced that the arrow on its frame be pointed in the direction of the air flow. Placing the arrow in the wrong direction will reduce the effectiveness of the filter.

With the chambers, filter(s) and burners of the furnace completely clean, it's time to oil the moving parts. A central gas furnace uses gas flames to heat air in a chamber. The heated air is then distributed to supply ducts by an electric fan. The fan rests in two bearings, one on each side of the furnace. Without proper oil, the fan bearings will quickly wear out. As they begin to wear, resistance increases and the motor must work harder to turn the fan. Oiling the bearings will not only make them last longer, but will reduce operating costs, as well. A few drops of a lightweight oil such as SAE 20 is recommended for most furnaces. Check manufacturer's instructions to be sure. Also, be careful not to overfill oil ports. Doing so can create a dust and dirt catcher.

There is an adjustment that will improve the operating efficiency of the blower system. Adjusting the fan belt will prevent fan-blade slippage and, in some cases, will eliminate noise too. You will need a screwdriver and a pair of pliers or a wrench to make the adjustment. A bit of slack in the belt ensures that there isn't too much pressure on the bearing, but it should be tight enough to do the job without slipping. Again, refer to your owner's manual to determine the proper amount of slack.

Finally, use duct tape to seal all duct connections air-tight. It doesn't make sense to heat the attic or subarea if they are not in use.

You can significantly reduce the cost to heat your home by properly maintaining your furnace.