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Why is My Furnace Filter so Dirty? Reasons Why it Might Clog Faster than Usual

small_14078798166The air filter that you have installed in your furnace is designed to last for a specific amount of time. Some filters are supposed to last for just 30 days, while others might say they can go 3 months without needing to be changed. But does it seem like your filter gets clogged much faster than the manufacturer says it’s supposed to? Today we’re going to help you figure out why this might be happening by answering the question, “Why is my furnace filter so dirty?”

 

Why is my furnace filter so dirty?

 

    • You’re using a cheap filter. As we mentioned above, some filters are only designed to last about 30 days. A month can go by quickly, so you might be surprised at how much dirt can build up on your filter over that time period. If some of the other factors below come into play, your filter might get dirty even quicker than that. If you’d like a filtration system that lasts longer, consider installing a whole house air cleaner.

 

    • It’s been colder than usual outside. Your filter gets clogged faster when your furnace is running more often. That’s because more air is cycled through your filter when your furnace goes through more heating cycles, so more contaminants get caught on the filter’s media. The colder it gets outside, the faster your filter will get clogged with dirt. That’s why it’s extra important to check on your filter every month during winter.

 

    • Your furnace’s fan is set to “on.” If the fan setting on your thermostat is set to “on” instead of “auto,” your furnace’s fan will constantly be running. This means that your filter will collect contaminants 24 hours a day, and it will get much dirtier than it would if you used the “auto” setting instead (which only turns the fan on during heating cycles).

 

    • Return vents are near sources of dirt and dust. The location of your home’s return vents can contribute to the amount of dirt that builds up on your filter. If any of those vents are located near sources of dirt and dust, those contaminants will get sucked right in and build up on your filter. Try to keep the area around your return ducts clean to avoid this issue.

 

    • You home’s air has a lot of contaminants. Some homes naturally have more contaminants in the air than others. For example, if you have one or more pets in your home, pet dander can quickly build up on your filter. In addition, the more people you have living in your home, the more dirt will get kicked up into the air and collected by your furnace’s filter. If your home naturally has a lot of contaminants, you should consider installing a more advanced air filtration system.

 

If you have any questions about why your furnace filter is so dirty, or if you’d like a heating system serviced or installed in your home, contact Jerry Kelly, your St. Louis furnace installation and repair contractor. We provide service all over the St. Louis area, including towns like Clayton, Cottleville and Creve Coeur, MO.

 

photo credit: NMEnergy$martAcademy via photopin cc