The Heat is on: Seasonal Maintenance to keep your Furnace Running its Best


Cold weather is upon us once again, so you've undoubtedly put your furnace to work for the winter. To perform its best, your heating system requires a bit of TLC now and then. We've assembled some simple tips and suggestions to keep you warm and toasty while Jack Frost is nipping at our heels.

*Before performing any furnace maintenance, be sure to shut off both the power to the unit as well as the fuel supply. When maintenance is complete, restore power, reconnect the fuel supply, and ignite the pilot if necessary.

This job sucks

Using a long, narrow attachment to vacuum dirt and debris out of the base of the furnace, away from gas burners, and out of any nooks and crannies can help keep it performing efficiently. (A long, snorkel attachment works best.) With electricity and fuel shut off, open up the furnace door and suck up any unwanted junk.

Burn the midnight oil

Proper lubrication will keep the furnace's blower motor running smoothly and prevent it from overheating. Because many older furnaces do not have bearings that are permanently sealed, it is important to lubricate them annually.  To reach the ports to add oil, you will probably need to slide or unscrew an access panel. Place a few drops of lightweight, household oil in the spout below the oil caps. For best results, be sure to use 10-weight (non-detergent) motor oil.

Think dirty thoughts

When it gets cold enough to require the daily use of your furnace, keeping its filters debris-free is one of the simplest ways to ensure peak performance and energy efficiency. Perform a monthly check to see if filters are dust-free, and if the filter has become truly filthy, replace it. If your furnace uses fiberglass or paper filters, there will probably be removal and installation instructions printer on the filter frame. Replacing common filters is usually as simple as sliding the old one out and sliding a new one in. Reusable foam filters can be removed and vacuumed or washed to remove dust. Better to replace an inexpensive filter than to compromise safety and pay higher heating bills due to inefficient operation.


Your fan belt that drives your furnace blower needs to be in good working order, or heat will be unable to make its way from the furnace to other parts of the house. Inspect belts for glazing, fraying, or cracking that may cause it to break or move improperly. The belt must also be set at the proper tension to work correctly. If you are able to push down the belt more than ½ to ¾ inches, it needs to be tightened. Simply loosen the bracket, move the motor assembly to tighten the belt, and retighten the bracket.

Check your furnace's temperature

If your furnace is not working probably, it could be for a number of reasons. One of the most common problems is an improperly set thermostat. Be sure that you have your thermostat set for heating, and check to see that the temperature is set appropriately by turning the setting up or down as needed. If this does not solve the problem, you may have a broken thermostat which needs to be replaced.

Breaker, breaker

A blown fuse or tripped circuit breaker can also cause a furnace to malfunction. Replacing a blown fuse will require that you locate the proper fuse in your electrical breaker box, unscrew the old fuse, and screw in a new one. If the circuit breaker has been tripped, find your electrical service panel, locate the breaker which is off, or not completely on (it may show red to indicate that it has been tripped). Slide the handle all the way to the off position, and then slide it to the on position. If breakers trip repeatedly, contact your electrician to determine the problem.

C'mon baby, light my fire

If dirt or drafts cause the pilot light of your gas furnace to go out, it will need to be reignited in order to work properly. This happens most commonly in older units which do not have the ability to ignite automatically. You will need to locate the knob on the gas valve and be sure that it is set to "pilot." When this is done, press the pilot light button and hold it down for one minute. If the pilot does not fire up, of will not stay lit, there may be a problem with your thermocouple and gas is not flowing properly.

*Yearly professional maintenance is the best way to keep your furnace working its best.

Posted by: Ahmed Muztaba
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