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What to Do if My Furnace Constantly Shuts Off

The normal cycle for a furnace to maintain a comfortable temperature is usually 3 to 8 times per hour. Therefore, more frequent stopping and starting is a sign that the furnace has a lot of problems and it will not produce enough heat for the house. Whether you have a Toronto mid-efficiency furnace, or any other furnace, there are some of the reasons why your furnace keeps shutting off are:

Insufficient airflow due to clogged filter

A clogged filter restricts airflow in the heat exchanger, which results in overheating followed by a safety shut down. One of the things to do if the furnace keeps turning on and off because of dirt is to clean or change the filter. It should be done at least every three months, but cleaning should be according to the recommendations of the manufacturer.

Another feature to look at is the air vents. Closed vents can result in insufficient air reaching the room while hindering airflow in the furnace. Having disposable filters in the house and knowing how to replace them is the best solution. You can also inspect and maintain the furnace regularly. Opening the vents and cleaning the blower wheel are other remedies.

A dysfunctional thermostat

The thermostat component usually communicates with the furnace to turn it on or off, depending on how you adjust it. It has settings and sensors that make using it and controlling the room temperature easier. That is why it is a viable reason why my heater keeps turning off when it is not working. To find out if the same applies to you:

  • Check the thermostat setting to ensure it is on and is on the HEAT status. Make sure the temperature is not lower than what you prefer.
  • Turn the thermostat from LOW to HIGH as you listen to the furnace. If it produces sounds, the furnace could be having the problem and the furnace repair could help; otherwise, the thermostat is the damaged one.
  • Changing the position of the thermostat can also be helpful. It should not be near a direct source of heat like a stove. If not, the furnace will be too hot and signal the furnace to turn off even if the house is still cold.
  • The thermostat should be at least 1.5 meters high and should not be close to drafty windows and doors. It should also communicate with the furnace effectively to ensure there are no delays in signal transmission.

A dirty or rusted flame sensor

A flame sensor has the role of shutting off the furnace if flames are not detected. It prevents dangerous fumes from reaching the indoor air, which helps maintain the air quality and prevents possible health issues. Because of its role and position, the flame sensor can be covered in soot or become corroded. Either of these can stop its functionality, which means it will not detect flames as it should. It may end up shutting down the gas valve supplying the furnace, even if it is functioning properly.

Wrong furnace size

Another answer to why my gas furnace keeps turning on and off question is the wrong furnace size. The size of the furnace is usually determined by its output, which should depend on the size of the room or house it will supply with heat. The furnace should not provide too much or too little heat; otherwise, it will use too much fuel to heat the room quickly, then the heat will subside just as fast, leaving the room cold. The thermostat will read the set temperature in the room and cause the furnace to shut off.

After the room cools, the thermostat will again trigger the furnace to turn on, causing a short cycle that takes a toll on the furnace and does not provide the comfort level needed in the house.

The best solution if the furnace flame keeps shutting off because of this is to buy a new furnace of the right size. It will also be more energy-efficient and consistent in its performance. If you cannot choose one on your own, call Air Makers, and a professional will guide you through the buying process.

Get reliable heating solutions

The best solution is to buy a new furnace of the right size if the furnace flame keeps shutting off. Air Makers can help you get long-lasting furnace solutions, which will keep you comfortable throughout the year and prevent a miserable experience.

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