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Can a dirty furnace filter cause no heat?

Often an overlooked furnace component, your air filter plays a significant role in preserving your indoor air quality. So, what happens when dirt, hair, dust, and other contaminants get stuck in the filter? Could a dirty filter be the reason why your home has suddenly turned into an ice box? If these are some of the questions on your mind, you've come to the right place.

Join the Anchor Home Comfort team as we go over the ins and outs of furnace filters and whether they could be the culprit behind your lack of indoor heat so you can create a warm home for you and your family members as soon as possible.

What are the symptoms of a dirty furnace filter?

A dirty furnace filter can display multiple signs that indicate it needs to be cleaned. The following are typical signs that it's probably time to replace your furnace filter:

Diminished air circulation

One of the main signs is a noticeable decrease in airflow coming from the vents that lead to various rooms throughout your home. You may have limited airflow from a dirty filter if your house doesn't seem as warm as it usually does or if some rooms are colder than others.

High heating bills

Dirty furnace filters makes your furnace work harder to keep the temperature where it wants to be, which increases energy usage. If you notice a surge in your monthly heating bills, a dirty filter may be the cause. 

Uneven heating

It's possible for specific rooms in your house to have considerably colder temperatures than others. This unequal heating distribution is frequently caused by a filter obstructing the hot air's normal path of circulation.

Furnace overheating

When the furnace overheats, the burners will shut off due to a limit switch being triggered. This can be caused by a clogged filter. Your furnace might be having trouble handling too much heat as a result of a dirty filter if you see that it cycles on and off frequently.

Strange sounds

When the system strains to get air through the clogged filter, a dirty filter may produce strange noises like whistling or rattling.

System short cycling

Short cycling occurs when the furnace turns on and off more frequently than usual. This can result from a dirty filter, causing the system to overheat.

Visible dust and dirt

A brief look at the filter will indicate its what state it is in. It is obvious that it needs to be replaced if it is obviously unclean or blocked with dust and debris.

Poor indoor air quality

A dirty air filter will circulate airborne particles that can lead to dry eyes, itchy skin, sore throats, and more. If you notice that your indoor air quality has diminished and you're experiencing an increase in allergy-like symptoms, it's likely that your heating system has a dirty air filter that needs to be replaced.

Why is my furnace running but not heating?

If your furnace is operating but not generating heat, there could be a few different problems. The following are some typical causes of this issue:

·  Problems with the thermostat: The thermostat may not be communicating with the furnace properly if it is malfunctioning or if the batteries are dead.

·  Unclean or clogged furnace air filter: A blocked air filter can impede air circulation, which can lead to overheating in the system and activate the limit switch, which will turn off the burners.

·  Issues with the pilot light or ignition: The burners in a gas furnace might not ignite if the pilot light is out or if there are other ignition-related problems.

·  Blocked vents or ducts: Inspect the vents or ducts for any other blockages that might be impeding the appropriate circulation of the hot air.

·  Bad limit switch: If the limit switch isn't working correctly, the furnace can shut off before it reaches the right temperature.

·  Problems with the blower motor: The warm air may not be circulated if the blower motor is not operating correctly.

Can a dirty air filter cause a furnace fire?

Although a dirty furnace filter won't likely start a fire on its own, it can lead to other potentially dangerous situations that lead to more furnace problems that lead to fires. Here is a closer look at how a malfunctioning furnace with a clogged air filter can cause a fire in your home during the winter season:

·  Reduced circulation: Your HVAC system will need to work harder to circulate air because a clogged air filter essentially inhibits airflow from the unit, which will negatively affect your home's temperature. Because the furnace needs to work overtime to reach and maintain a comfortable temperature indoors, internal components like the bower fan and other components can experience high amounts of strain, leading to overheating of your equipment.

·  Broken or cracked heat exchanger: The heat exchanger may get cracked as a result of overheating, which in turn can cause a carbon monoxide leak into your home. A cracked heat exchanger is a serious issue that requires an immediate HVAC repair.

·  Ignition of debris: When exposed to high temperatures, dust, accumulated particles, and other materials inside and around the furnace can catch fire.

To avoid dirty filters that may cause fire hazards and furnace damage, we recommend continuously replacing your air filter in your HVAC unit. Depending on the size of your home, how often you use your furnace to keep your home warm, and other factors will impact how often you install a new filter.

That said, a clogged air filter should be changed every one to three months.

How do you reset a furnace after a dirty filter?

Use these general procedures to reset your furnace after replacing a filthy filter to make sure it runs as efficiently as possible.

1. Find the furnace's power button or circuit breaker, then flip it off. This will keep you safe while the reset is being performed.

2. Give your furnace a few minutes to sit.

3. Make sure that the old, dirty air filter has been correctly replaced with a new, clean one. Verify that the access panel is firmly closed and that the air filter has been installed correctly.

4. Restart the furnace's power supply. You have two options: reset the circuit breaker or use the power switch.

5. Adjust the thermostat to the preferred setting. The heating cycle should be started as a result, and the furnace will start using the fresh, clean filter.

Change Your Air Filters with Anchor Home Comfort Today!

When was the last time you had your furnace air filter changed? If you can't remember, or it's been well over a year, the team from Anchor Home Comfort is here to help! Our certified 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.

Anchor Home Comfort is delighted to work with homeowners throughout Arnprior, Clarence, Bishop Mills, Ottawa, Casselman, Gloucester, Embrun, Cumberland, Manotick, Orleans, and Rockland.

Say goodbye to cold spots, and hello to fresh air in your home! If you live in one of these areas, reach out to the team to schedule your maintenance appointment today! You can contact us directly over the phone or use our online booking form.

Work With Our Local Experts Contact Anchor Home Comfort For A Free Quote On Your Ottawa Heating, Cooling, Plumbing or Electrical Installation

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