How To Clean A Gas Furnace

How To Clean A Gas Furnace

Do you feel the chill of winter creeping into your home? Is cozying up to the fire or wrapping yourself up in a blanket the only way to keep warm? If so, your gas furnace might need some TLC.

Keeping your gas furnace working at peak performance requires preventative cleaning and maintenance. This is the best way to get the longest life and reliability out of your home heating system.

So how do you clean a gas furnace?

If you want to keep your system running efficiently, you can use these gas furnace cleaning tips.  

Step #1: Gather up your tools

To do the job, you’ll need some essential tools including:

  • Screwdrivers
  • Ratchet & socket set
  • Vacuum preferable a shop vac, but can be any vacuum with an upholstery brush attachment
  • Small, stiff-bristled brush
  • New furnace filter
  • Emery cloth
  • Drinking straw
  • Lightweight machine oil

Get them all together so you don’t have to keep stopping your work to find the right tools.

Step #2: Turn off the furnace power and gas

This is important to reduce the risk of shocks or gas leaks. First, turn off the furnace power source found in your circuit breaker box. Next, switch the furnace’s electrical power to off. Then, shut off the gas valve with a ¼ turn.

Step #3: Clean the surfaces

Start with the exterior surfaces, wiping them down with a clean damp rag. Next, remove the furnace access door, which usually comes off if you lift it up and out. If you have a burner cover, you’ll have to loosen the screws to remove it. Use a vacuum to clear away dust from the burners and furnace base. Try to get every surface, including the compartment behind the blower door. Just lift it and reach in with the vacuum nozzle. If you notice any soot, or dark dust build-up, stop the job, and give your local gas furnace expert a call. This means there’s something wrong with combustion.

Step #4: Remove and clean the blower

You’ll probably have to unscrew the control panel as it most likely is blocking the blower. Use a socket and ratchet to remove the bolts holding the blower in place. Take the blower out carefully and avoid touching the wiring and counterweights on the fan blades. Gently use the vacuum to remove dust, and if necessary, use a small brush to wipe off anything that the vacuum doesn’t remove. Although you can do this yourself, a professional will make sure that the cleaning removes all the dirt or else the system can be thrown off balance.

Step #5: Clean the pilot or hot surface igniter

Use the straw to gently blow dust off the pilot light to make sure your readings are accurate. If your furnace is a newer model, it might have a hot surface igniter instead. If so, don’t touch it. You can still use the straw to blow off dust.

Step #6: Clean the flame sensor

The flame sensor is in a bracket. Pull it out and use your emery cloth to clean it to help ensure your furnace lights properly. Slide it back into place.

Step #6: Inspect the drive belt

Look for signs of cracking or fraying on the drive belt. If it seems damaged, you can purchase a new one and replace it. When you make a replacement it should be tensioned to deflect ½-3/4-inch.

Step #7: Lightly lubricate

Remove the oil caps and clean them and then use no more than 2 to 3 drops of lubricating oil on the two blower motor and shaft bearings.

Step #8: Replace the air filter

Remove the oil furnace filter and replace it. This should actually be done every three months. Always choose a filter based on manufacturer recommendations or else you might strain the blower motor.

Step #9: Activate the burners

Once complete you can turn everything back on. To activate the burners turn up your thermostat and then make sure the burner flames are even and blue. If the flames are yellow, you have dirty burners. This is a problem and needs a professional maintenance person to come in and clean and adjust them.

Step #10: Adjust the dampers

Last but not least, if you have a heating and cooling system, you have to adjust the dampers for seasonal settings.

Find Long-Term Solutions

If this seems like a lot of work, it might make more sense to schedule a gas furnace maintenance call. This is where we come in. As your Mount Vernon gas furnace experts, the team at Mount Vernon can provide gas furnace maintenance, repairs, and replacement so you stay toasty warm all winter long! Give us a call today!

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