In December, night temperatures begin to drop into the 30s. Before you’re hit with a hard freeze, make sure your heater is in good working order. Our Furnace Maintenance Guide outlines steps you can take to ensure your nights remain toasty warm.

The following checklist applies to natural gas and propane-fueled furnaces. Your furnace may vary, so download the manufacturer's product manual for specifics if possible.

Step by Step Checkup

Furnace maintenance mainly includes inspection and cleaning the machinery.

1. Access and check the burners

Turn off electrical power and open the combustion chamber access door. Then, remove the burner cover, if applicable.

Turn on the power again and check the burner flames. If flames are even and blue, they’re fine. If they are burning yellow, call a professional for a burner adjustment.

Then, turn off the power and shut off the gas.

Examine the chamber for signs of soot and vacuum the burners to remove dust.

2. Remove and clean the blower

The blower is normally located behind the air filter. Remove the blower with a socket wrench. You may need to disconnect the electrical wires that power the fan.

Clean the blower by removing dirt from the blades with a small brush and vacuuming up any residue. Avoid disturbing the counterweights on the blades.

If the motor has oil ports, lubricate it by using the oil recommended by the manufacturer.

Inspect and clean the belt. The blower fan belt should be firm and free of damage. If cracked, replace the belt.

Vacuum the compartment, reinstall the blower, and change the furnace air filter.

3. Clean the igniter

Clean the pilot light using canned air and the included tube straw. Then remove the flame sensor and clean it of residue with a dry cloth.

For furnaces with hot surface igniters, remove any dust with canned air and tube straw.

4. Check the exhaust

Inspect the flue for obstructions, leaks, or cracks. A leaky flue could result in the release of carbon monoxide in your home. If damaged, call in a service tech.

5. Clean out vents and register.

To improve the air quality in your home, use a vacuum to clean out air ducts. Clean vent covers or registers with hot, soapy water.

6. Check the thermostat to ensure it switches onto heat when set.

You may want to also change the battery in your thermostat and carbon monoxide detector.

When to Call in a Pro

If you feel uncomfortable about performing any of these steps yourself, don’t hesitate to call in a professional technician.

Make an appointment with the professionals at One Hour Heating & Air Conditioning in Chattanooga. Let the pros provide your annual furnace maintenance, safely, quickly, and effectively.