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Reasons Why Your Furnace Might Not Be Working


A furnace is the most important appliance in your house, especially during the cold weather. Many issues can cause your furnace to stop working. Regular maintenance and timely repair will ensure your furnace is running efficiently. Count on Aire One Heating & Cooling Kitchener-Waterloo for quality installation and repair of your furnace systems. We have been providing furnace and heating systems to our residential and commercial clients in Kitchener-Waterloo, Guelph, Cambridge and Stratford since 1990. Your furnace might not be working due to any of the following reasons:


1. Dirty Filters

Clogged and dirty air filters can disrupt the proper airflow in your furnace and lead to overheating. Air filters trap household dust, dirt and pet hair that can clog your filter over time and prevent it from working efficiently. Regularly replace your air filters to maintain the air quality in your home.

2. Malfunctioning Thermostat

Check your thermostat setting to ensure it is running on a temperature that is five degrees higher than the room temperature. Make sure the switch is on ‘Heat’ and it is displaying the right day and time. Additionally, check your thermostat for batteries; your display might go blank when batteries die.

3. Insufficient Gas Supply

Examine if the gas valve is turned on by observing the shut-off valve. If the supply is disrupted, your furnace might not be getting the necessary fuel to ignite. If you detect a gas leak, call a professional to evaluate the issue.

4. Faulty Pilot Control or Electric Ignition

Gas furnaces operate with a pilot light or an electronic ignition system. In systems with a pilot light, the thermocouple might be faulty, loose or might need adjusting. For ignition systems, turn the power switch off and on again to reset the ignition control.

5. Lack of Maintenance

Identify problems in your furnace with annual maintenance. Lack of maintenance is the primary reason for malfunctioning furnace. Check for:

  • Blower motor issues – A green light indicates working system, red or not blinking indicates issues

  • Dirty burners – Rumbling noise in the furnace indicates a faulty burner

  • Flame sensors – Flame sensors might be faulty if sensors are corroded or cracked or if the furnace shuts down after lighting for a few seconds

6. Circuit Breaker

Check the circuit breakers to ensure they are in the ‘ON’ position. Depending on the issue, tighten electrical connections or replace the breaker. If you notice any of the circuit breakers not functioning or if they are tripping (caused by a short circuit), call a professional for repair. Also, make sure your furnace is not running with other larger electrical equipment, causing it to overload your circuit. Aire One Heating & Cooling Kitchener-Waterloo provides installation, replacement and repair services of your furnace systems in Kitchener-Waterloo, Guelph, Cambridge and Stratford. We also offer air handlers, boilers and heating repairs for residential and commercial clients. Contact us today for the maintenance and repair of your furnace systems.

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