Common Furnace Problems to Watch Out For

Fall has arrived and with it comes colder days and nights.  Unless you want to bundle up in multiple sweaters or sleep with mittens on, you must make sure your furnace stays in good working order.  If the heat is not flowing properly, it may be due to one of these problems:

Clogged Filters

The filters in the furnace collect dirt over time and can easily get clogged.  Clogged filters restrict the airflow, making the furnace less efficient and causing more wear and tear on the unit as it must work harder to reach the desired temperature.  Remember to regularly change the filters in order to avoid this problem.

Dirty Flame Sensor

The flame sensor is a thin metal rod that detects the presence of an actual flame when the gas valve is open.  When the burners are ignited, but the flame sensor does not detect a flame, the unit will shut down automatically.  Over time, the sensor can get dirty from carbon buildup, causing it to misread and continually shut down the system.  Simply removing the flame sensor and sanding it down with a bit of sandpaper or steel wool may restore the furnace to working order.

Faulty Thermostat

The thermostat is the core of the heating system because it controls how much heat is produced.  To determine if there is a problem with the thermostat, raise the temperature on the control panel by at least 5 degrees to see if the unit starts up.  Also check to make sure the switch is correctly set to “heat”.  Malfunctioning thermostats can be caused by faulty wiring so tightening loose wires or mounting screws may correct the problem.

There are a number of other mechanical malfunctions that can cause a furnace to stop working properly, such as broken belts, worn out blowers, bad heat exchangers or broken fan motors.  Regularly maintaining your furnace is the best way to detect early signs of a problem and repair them before it’s too late.

When buying a home, you want to make sure that components such as the furnace are in good working order.  Lakes Area Home Inspections will look at the visible portion of the heating system and its components and will inform you of any noticeable defects.   Contact us at 262-818-0911 when you need a reliable, experienced inspector to provide an honest opinion of the condition of a home.


LAHI serves the entire area of Northern IL and Southern WI.  If you are in Lake Bluff, Ringwood, Gurnee, Arlington Heights or the surrounding areas, give us a call at (224) 334-8885 so we can get you on our schedule

Referenced articles HERE and HERE

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