Troubleshooting Your Furnace

Posted on: 13 October 2015

The fall season is in full swing and winter is just around the corner. The last thing you need is for your furnace to be sidelined by common problems when you need it most. Here are 4 all-too-common issues that could put a wrench in your seasonal heating plans, as well as how to prevent those issues from leaving your home in the cold.

Malfunctioning Thermostat

Thermostat failures are usually the most common type of failure for a typical furnace. For starters, most thermostats rely on AA or AAA-size batteries for their power. If the thermostat display appears to be blank,or if the thermostat itself refuses to respond to any inputs, you should swap the existing batteries out for a fresh and fully charged set.

An improperly wired thermostat can also cause problems. If you have access to the wiring scheme for your furnace's thermostat, then you should make sure it's wired correctly to the furnace. If you don't know how your thermostat is wired and you don't have a wiring scheme on hand, then you should have your HVAC technician inspect the wiring on your behalf.

Blower Fan Motor Failure

There's plenty that can go wrong when it comes to your blower fan motor. For instance, the rubber belts that drive the fan can wear out and snap. Poor or nonexistent lubrication can also cause fan motor bearings to run dry and eventually burn out. Rust, corrosion and general fatigue can also wear down the blower fan motor after years of constant use.

Here are a few ways you can make sure your blower fan motor stays in good shape:

• If your furnace uses a belt-driven fan instead of a squirrel cage, check the condition of the drive belt. Replace the belt if it appears cracked or frayed or has a glazed appearance.
• Make sure the blower fan motor is properly lubricated. If the fan motor sounds rough as it drives the blower fan, or if it has trouble engaging, then you should have your HVAC technician replace the motor.
• Don't forget to check the state of the fan blades. The blades should be free of any cracks, dents or other signs of damage or fatigue.

Heat Exchanger Failure

On gas and oil-fired furnaces, heat exchangers are essential for transferring heat from combustion gases to the surrounding air without allowing toxic gases to escape. Unfortunately, the constant exposure to heat and other stresses can cause cracks to form along the surface of the heat exchanger. Rust and corrosion formation can also eat holes in the heat exchanger if given enough time and exposure to moisture.

Cracks and holes are the last thing you'd want in your heat exchanger, since it provides carbon monoxide (CO) with a handy escape route into your living spaces. It's important to inspect the heat exchanger for cracks as well as signs of rust and corrosion. If you do happen to see any damage, then you should turn your furnace off and call your HVAC technician as soon as possible.

In addition, is also helpful to have a carbon monoxide detector installed in your home. That way, you can have plenty of warning of any CO leak before it poses a serious risk to your health and well-being.

Heating Element Failure

Unlike a typical gas or oil-fired furnace, an electric furnace uses a series of electric heating elements to create and distribute warm air throughout your home. A heating element failure could occur if the wiring leading to the element breaks due to age or excess wear and tear. The actual heating element can also fail with time.

If your electric furnace suffers a heating element failure, then you should get in touch with your HVAC technician. It's usually not advisable to attempt to replace the heating elements on your own, due to the increased risk of electric shock.

For more information, contact a local furnace repair technician.