How to Double the Life of Your Furnace

Change a Furnace Filter

Your furnace may be big, bulky, and perform one of the most essential tasks in your home, but that doesn’t mean it needs to be intimidating. Many regular furnace maintenance tasks can be done by homeowners and changing the furnace filter is a simple one that will save money and prolong the life of your furnace. Here’s how.

Plus: Simple Furnace Fixes You Can Do Yourself

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Make Sure the Chimney Exhaust Flue is Clear

Drawn by the warmth, birds sometimes fall into the chimney exhaust flue. Turn the furnace off and the thermostat all the way down, then dismantle the duct where it exits the furnace and check for debris. Be sure to reassemble the sections in the same order and direction that you took them out.

Here’s how to tell if you need a new furnace.

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Flush Out Drain Lines

High-efficiency furnaces can drain off several gallons of water a day in heating season. If the drain lines become restricted by sediment or mold growth, the furnace will shut down. If the drain hose looks dirty, remove the hose, fill it with a mixture of bleach and water (25 percent bleach), then flush it after several minutes.

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Look For Blocked or Leaky Ducts That Can Restrict Airflow

If your furnace comes on but one or two rooms are cold, first make sure all the room registers are open. Then examine any ductwork you can get access to and look for gaps between sections or branching points. Seal any gaps between sections of duct with special metal duct tape. Don’t use standard cloth duct tape—it quickly deteriorates, and it may also cause ducts to leak if it was used to seal sections in the past.

Also check for handles protruding from the ductwork. These are dampers or air conditioner bypasses—make sure they’re open. Learn more about working with round duct work here.

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Clean Away Leaves and Debris From Heat Pumps or Intake and Exhaust Vents

If you have a furnace that vents out the side of the house, make sure nothing is blocking the intake or exhaust. If either of the pipes is covered with screen mesh (like window screen), replace it with 1/2-in.-mesh hardware cloth. If ice is clogging one of the pipes, you have a bigger problem somewhere in the system. Clear it off and call a technician to find out why it’s happening.

If you have a heat pump, clear away grass and leaves from the fins of the outdoor compressor unit. Before heating season starts, hose it down gently from the top to rinse dirt and debris out of the housing.

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Inspect the Burner Flames

Turn the power furnace switch on and activate the burners by turning up your thermostat. Inspect the burner flames. The flames should be fairly even and blue. Yellow flames indicate dirty burners. (Don’t breathe on the flames because the extra oxygen will also make them turn yellow.) Don’t adjust the burners yourself. Call in a pro.

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Vacuum the Burners

Turn off the power switch again and shut off the gas by giving the valve one-quarter turn. Vacuum the burners and the furnace base. To get at the back of the burners, tape a 20-in. length of 1/2-in. drain line to your vacuum hose. Vacuum everywhere you see dust. While everything is open, use a flashlight to look for signs of soot (fine black powder), which often indicates poor combustion. Lift off the lower door (blower door) and vacuum the blower compartment.

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Clean the Blower

Clean the blower blades thoroughly with a vacuum and small brush. Take care not to stress the wiring or disturb the counterweights that will be on the fan blades. If you can’t clean the blower thoroughly, don’t clean it at all; you could throw it off balance.

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Clean the Pilot

Blow dust off the pilot. Direct air to the exact spot by blowing through a drinking straw. A dirty pilot can cause the flame sensor (or thermocouple) to get a false reading that the pilot isn’t lit. Some newer furnaces have hot surface igniters instead of pilots and electronic igniters. (Note: One burner was removed for clarity.)

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Clean the Flame Sensor

The flame sensor occasionally becomes coated with residue and will prevent your furnace from lighting. Remove it by pulling it down out of its bracket. Lightly clean the surface with fine emery cloth and slip the sensor back into its bracket.

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Clean Hot Surface Igniters

Hot surface igniters are the most common ignition system on furnaces being manufactured today. They take the place of standing pilot lights and electronic igniters. Clean the dust off the hot surface igniter by leaving the igniter in place and blowing air through a straw. This part breaks very easily; don’t even touch it. In fact, when you replace the furnace doors, do so gently to avoid breaking the igniter. You can also double the life of your air conditioner with these tips.

If you’re looking for the best furnace to purchase, energy efficient brands might be the best bet.

Do you have a room that’s a little colder in the Winter or warmer in the Summer? Check out this simple blower speed furnace boost trick.