Anonymous asked in Home & GardenMaintenance & Repairs · 1 month ago

Does a clean AC air filter need to be changed and why is it clean after 2+ months?

I used exactly same make of AC filter.  It seems like during winter, it catches plenty of dust as it become dirty after 2 months, but during non-winter season like now, it's still very clean after 3 months.  1) Does the AC filter still need to changed following manufacturer recommendation even if it's clean?  2) And if it's clean after 2+ months in summer, what does that mean?  (During winter, it seems to have caught plenty of dust).


This is for residential central AC system.

8 Answers

  • 4 weeks ago

    Just keep it clean at all times, if it is past the manufacturer recommendation then change it, it may be trapping microscopic germs and mould spores, definitely don't want to be breathing them. 

  • 1 month ago

    IF the filter isn't dirty, don't worry about it. If the filter GETS dirty, change it. Just keep an eye on it. 

  • Anonymous
    1 month ago

    Dust and other substances make it wait.

  • 1 month ago

    In winter people track in mud that turns to dust. In the summer, no mud, and you have a cleaner house. Personally I would keep using the clean filter.

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  • Droopy
    Lv 5
    1 month ago

    Where do you live? What type of filters fiberglass, polly, or pleats?  I'm in Virginia an your usually looking  at a month winter or summer usually less in tge summer.   But it bassed on the usage and living area.

    I do hvac pms sone buildings your lucky to get a month others after 3 months there still pretty clean.

  • Anonymous
    1 month ago

    Check and double check if you have the correct filter and you installed it correctly (check the arrow).  Do not change filter if filter is clean.

  • 1 month ago

    Two possibilities.


    1. The filter is not fitting properly and much of the air is bypassing the filter.


    2. In the Winter the air can be much drier that can let static electricity collect on the filter. That can make the filter better at attracting dust to it. 

  • Paul
    Lv 6
    1 month ago

    That makes no sense unless you live in Australia.  No, you don't need to change a clean air filter.

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