With cold weather approaching, it's time to inspect your home heating system to make sure that it's safe and in peak operating condition. No furnace will keep functioning efficiently without regular maintenance. Ideally, the furnace should be inspected by a heating professional at least once annually just before its initial start-up for the season. Many heating companies offer annual maintenance contracts with a new furnace. This service is also available for older furnaces which often require a bit more maintenance. Even if you do your own annual maintenance, the system should be inspected by a heating professional every three to five years.
The first step in a furnace tune-up is filter replacement. Always be sure that the power to the unit is turned off before attempting repairs. The filter acts to protect the blower from airborne dust and dirt which would damage the motor. The filter also helps to reduce the amount of dust discharged throughout the house. When the filter becomes clogged, it makes the furnace motor work harder and results in greater cost and less efficiency.
The filter typically is located where the cool air enters the furnace; just behind the grill at the cold air return, at the entrance to the blower chamber or sometimes at both locations. For most furnaces, the filter slides in and out.
Filters come in many shapes and sizes. Thus, it's a good idea to bring along the old one when replacement shopping. Don't buy one filter, buy a full case about a dozen. The per filter price drops significantly, and you'll have replacement filters handy. You'll need to replace it every one to three months of blower use. Homes with pets or those located in dusty areas require more frequent filter replacement.
Once you have the furnace filter removed and before you install the replacement filter, it's a good time to tidy up the blower compartment. Use a vacuum cleaner with an upholstery brush attachment to remove dust and debris. Using the vacuum, remove soot and other debris from the interior of the fire box or burner chamber. Use caution when working at the interior of the burner chamber as many are lined with fibrous material.
Housekeeping should not be limited to the filters, the blower compartment and burner chamber. It should extend to the ducts and cold air return as well. This is more of a health issue than one of efficiency. This is of special importance to persons with respiratory ailments or allergies.
Dust, dirt, pollen, animal dander and other airborne contaminants are pulled into the ducts each time the blower is operated. These contaminants build up inside the ductwork over time and can make the duct system an ideal breeding ground for mold spores, bacteria and foul odors.
Duct cleaning cannot easily be done effectively by the do-it-yourselfer. The process, which costs approximately $300 to $500 for the average home, uses a powerful portable vacuum along with an "air snake" that is fed through all of the ducting. The air strips the interior of the ducts and feeds the debris into the special vacuum. This process should be performed every one to five years depending upon accumulation. Check with a heating contractor for a referral. Loose fan belts not only make the furnace operate less efficiently, but can make a racket as well. For most furnaces, fan belt tension can be adjusted at the motor brackets. A properly adjusted fan belt should "give" about half-an-inch. A badly worn belt should be replaced with a new one. Keep a replacement belt in the event emergency replacement is needed.
If the furnace is oil-fired, the bearing at the pump motor should be oiled with a few drops of a fine machine oil. The fuel filter in the main oil line should also be replaced annually. The burners should be checked every two to five years to make sure that they mix the correct amount of fuel and air for proper combustion. Smoke emission tests should be made for oil furnaces. Black smudges surrounding the door to the burner compartment are a sign of poor combustion and indicate the need for burner adjustment.
The replacement of the fuel nozzle on an oil-fired furnace with a smaller nozzle can greatly diminish it's fuel consumption. This technique is known as "derating" and causes the furnace to run for longer periods while consuming less fuel. Derating costs about $50 and is especially effective on energy-guzzling older furnaces.
As with an oil-fired furnace, the burners for a gas-fired furnace or boiler should be checked for proper combustion every two to five years by a heating professional. The heat exchanger should be inspected once each year for leakage or dangerous combustion gases. Many local utility companies will perform this service at no charge or for a modest fee. Whenever the smell of gas is present around the furnace, the gas supply to a gas-fired furnace or boiler should be turned off and the utility company or a heating professional should be notified. The system should not be used until it is inspected and repaired.
One way to make your gas-fired furnace more fuel efficient is to replace the pilot light with a new electronic ignition system. This can cost between $200 and $300, but will ultimately pay for itself in energy savings. A bonus is not having to relight the pilot each season or each time it blows out.
For homes with forced air heating, the ducts have a great deal to do with the overall effectiveness of the system. Many older homes have ducts that are rusted through and allow heated air to escape into attics, basements and crawl spaces. Poorly sealed connections and non-insulated ducts are other big energy wasters.
Damaged ducts should be replaced with new material. All joints and connections should be secured with screws and sealed with silver duct tape. Non-insulated ducts should be wrapped with insulation. Use a one-inch-thick fiberglass duct insulation. The material can be secured at the joints with silver duct tape.
