Can a dirty furnace filter cause no heat?

Your air filter is a vital component of your furnace and helps to maintain the quality of the air inside your home. That said, it can often be overlooked by homeowners. So, what happens when debris such as hair, dirt, and dust become trapped in the filter? Is there a chance that a dirty filter is to blame for your house becoming cold and uncomfortable? To learn more about your furnace air filter, keep reading.  

How do I know if my furnace filter is dirty?

There are several indications that a furnace filter needs to be cleaned. Here is a closer look: 

• Reduced airflow: One of the primary indicators is an apparent reduction in the airflow from your vents. If your residence seems cooler than it typically does, it may be because you have a dirty airflow.
• Increased energy costs: A dirty filter puts more strain on your furnace to maintain the desired temperature, which uses more energy. Your monthly energy bills might have increased because of this.
• Inconsistent heating: It is possible for specific rooms within your residence to experience cooler temperatures than others. The primary cause of this uneven heating distribution is a filter blocking the hot air’s regular circulation path.
• Overheating of the furnace: A limit switch will be activated, causing the burners to shut down. One possible reason for this is a blocked filter.
• Short cycling: If your furnace is turning on and off a lot, it may be struggling to handle the heat due to a clogged filter.
• Strange noises: A dirty filter may make odd noises like humming or rattling when the system attempts to get air through the obstructed filter.
• Visible dirt and dust: A quick inspection of the filter will reveal its condition. If it is visibly dirty or clogged with dust and debris, it is apparent that it has to be changed.

What is causing my furnace to not heat up?

There could be several issues if your furnace continues to operate but is not producing heat. The most frequent explanations for this include: 

• Issues with the thermostat: If the thermostat is broken or has low batteries, it might not be able to communicate with the furnace correctly.
• Problems relating to ignition or the pilot light: In the event that the pilot light goes out or there are additional ignition-related issues, the burners in a gas furnace may not light.
• Obstructed ducts or vents: Examine the vents or ducts for any further obstructions that could be preventing the warm air from flowing through them in the correct way.
• Defective limit switch: The furnace may turn off before it attains the correct temperature if the limit switch isn’t functioning correctly.
• Issues with the blower motor: If the blower motor isn’t working correctly, warm air can stop circulating.

Could overheating occur in my furnace due to a dirty filter?

Yes, if your furnace’s filter is blocked or dirty, there could be a risk of overheating. This is how overheating can be caused by a filthy filter:

• Diminished airflow: The furnace filter’s main function is to capture dust, dirt, and other airborne particles and keep them out of the furnace and its parts. Eventually, these particles block the filter, limiting the amount of air that can pass through the system.
• System stress: The furnace has to work harder to suck in air when the filter is dirty. The system strains to draw in enough air to heat as a result of the constrained airflow.
• Overheating components: The heat exchanger, in particular, may overheat as a result of the system’s increasing strain.
• Safety shutdown: Limit switches are among the safety features that come with furnaces. The limit switch turns off the burners when the system detects that the airflow is restricted and the temperature is rising dangerously, thereby averting further damage and possible safety risks.

It is best to speak with a licensed HVAC technician if you believe your furnace has been overheating or if you have experienced a safety shutdown. They can do a system inspection, take care of any underlying problems, and get your heating system back up and running correctly in no time.  

How do I reset my furnace after the dirty filter was changed?

To ensure that your furnace operates as effectively as possible, follow these steps to reset your equipment after removing and replacing your air filter: 

1. Locate the circuit breaker or power button on the furnace, then turn it off. This will protect you from any injuries as you go about changing your air filter.
2. Let the heating system sit for a couple of minutes.
3. Ensure that the new, clean filter has been installed correctly in place of the old, dirty one.
4. Make sure that the filter has been installed correctly and that the access door is securely closed.
5. Restart the electrical source for the furnace. Resetting the circuit breaker or using the power switch is how you do so. 
6. Change the thermostat to your desired temperature. As a consequence, the furnace should start the furnace e and use the new, clean filter.

If you are uncomfortable with changing the air filter in your furnace, reach out to a local HVAC company and request a maintenance appointment with a certified technician who will be able to perform the task for you.

Are you overdue for your filter change? If so, the professional HVAC team from Knight Plumbing is available to assist you! Our certified and experienced HVAC technicians are available for all repairs and maintenance services 24/7365 days a year, including after-hours, weekends, and holidays, at no extra cost. We also offer same-day repairs in emergency cases when a working furnace is imperative. 

Knight Plumbing is pleased to partner with homeowners throughout Cochrane, Langdon, Okotoks, Bragg Creek, Willow Park, Airdrie, Chestermere, DeWinton, and Deer Ridge. If you live in any of these communities, don’t hesitate to reach out and schedule an appointment with the team at any time!

You can give us a call directly or use our online booking form to reserve your time slot.