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How to Fix a Clogged Filter

How to Fix a Clogged Filter

A clogged air filter in your furnace is not just an inconvenience, it can cause escalating problems with your home's HVAC system. From poor performance to increased energy costs, a clogged filter is an HVAC problem that needs to be addressed without delay. Timely cleaning or replacement of a clogged filter will help to prevent contaminated air from entering the home, and can even prolong the life of your HVAC system.

What Does a Filter Do?

Your furnace's air filter works to clean the air in your home of particles such as dust, pollen, and smoke. It does this by drawing outdoor air through the ductwork of your home. As this air is brought into the furnace, it passes through the air filter. The filter catches and removes these particles from the air before it is sent through your home. The filter is only doing its job when the furnace is running. The main benefits of a properly functioning furnace air filter is that it improves the efficiency -- and longevity -- of your HVAC system, as well as making the breathing air of your home healthier.

Some problems that can occur when your furnace's filter is clogged include:

  • Increased energy consumption.
  • Reduced air flow.
  • Furnace working harder than usual.
  • Poor heating and cooling.
  • Air conditioner coils freezing.
  • Air that contains increased levels of dust and pollutants.
  • HVAC system burnout, and ultimately failure.

What Causes a Clogged Filter?

While a lack of maintenance can generally be implicated in causing a clogged filter, there are a number of other issues that can cause a blocked air filter. They include:

  • Using an inexpensive or poor-quality filter: Generally speaking, the better the quality of the filter, the more expensive it will be.
  • Colder than normal temperatures: The colder it is, the more your furnace runs. This increased usage can cause the filter to clog faster than it otherwise would.
  • The furnace's fan is left in the "on" position: If the furnace's fan is constantly running, rather than just automatically when it calls for heat, the filter will clog faster than it otherwise would.
  • Poor indoor air quality: Many occupants, and even pets can cause an increase in the amount of dust and allergens within a home.
  • Return air vents located in dusty or dirty areas: Contaminants will get sucked up, and pass through the air filter, if your return air vents are located near dusty or dirty areas. The more dirt and debris your filter needs to clean out, the quicker it will become clogged.

Now that we've explored what can cause a clogged air filter in your furnace, it's important to know the symptoms of a clogged filter. Knowing the signs of a clogged air filter allows homeowners to resolve any issues without delay. This helps to prevent contaminated air from entering the home and can help improve the efficiency and prolong the life of your HVAC system. Signs that you have a clogged filter include:

  • Vent covers filled with dust, dirt, and debris.
  • Return air registers clogged with dust.
  • Dust buildup within the furnace box.
  • Reduced air flow.
  • Poor heating and cooling.
  • Short cycling of the furnace.

How to Change a Clogged Filter

Changing a clogged filter is actually a very simple task that most homeowners can complete themselves, but can also be performed by a professional. In order to fix your clogged filter, you'll need to:

  • First, determine the type of filter you have and purchase a replacement.
  • Turn off the furnace and remove the old filter.
  • Replace with the new filter. Be sure to check that it is facing the correct way.
  • Close the furnace back up and turn it back on.

If your furnace has a reusable filter, you'll need to remove it and clean it yourself. You can do this by vacuuming up large particles, and then washing the filter screen with a mild soap and water solution. Let the filter air dry completely before reinserting.

How to Prevent a Clogged Filter

You can prevent a clogged furnace filter by making scheduled cleanings a part of your regular home maintenance. By taking a few minutes to clean or replace your air filter regularly, you can reduce your energy consumption, increase the clean air in your home, and improve the longevity and efficiency of your home's HVAC system.

You can also keep an air filter from clogging by ensuring that your ducts are cleaned regularly, the area around your intake vents is kept clean, and the area around your furnace is kept clean.

If you are not comfortable cleaning or changing the air filter in your furnace, contact a qualified HVAC professional in your area for assistance.