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How To Clean an AC Filter


A quality air-conditioning unit is very low maintenance, which is why the air filters are often forgotten. Yet, it is vitally important that the AC filter is regularly cleaned or replaced to maintain top performance.


What Are The AC Filters


Air conditioning units have filters installed to remove dust, debris and significant allergens from the air circulated through the room. It effectively cleans the air of pollutants, which is one of the fringe benefits of having AC installed in your home, apart from the cool and comfortable environment.


There is an abundance of different air filters, with each material having unique properties. It is recommended to look at the options for different filters when purchasing an AC unit, as you’ll often be restricted to only a few types due to the unit’s design. However, it is nearly always possible to replace disposable filters with the newer type of washable filters without affecting the performance of the AC unit.


Fiberglass filters are cheap and disposable, while plastic mesh filters are strong and washable; HEPA filters reportedly catch 99.97% of contaminants, including viruses and bacteria. Pleated fabric filters offer durability and excellent filtration, and electrostatic filters are ideal for catching dust and are easily cleaned by either vacuuming or washing.


The owner’s manual will contain a list of compatible air filters for your AC unit, including the recommended MERV rating. If you have successfully replaced the OEM filter with another brand or type of filter, it is good to keep the original packaging for future reference.


How Often Should You Clean The AC Filters


The recommended schedule for cleaning the AC filters is between four weeks or less for dusty environments or homes with many pets, to once a season. It is always good to start with a short schedule, which can be extended if the filters are not too grubby. The task of replacing or cleaning the filters is not serious, tedious or time-consuming, so there really is no excuse to delay the job until next week.

What Happens If The AC Filter Remains Dirty


If the AC filters are not kept clean, two things will happen: first, “dirty” air will continuously circulate, and second, unnecessary strain is placed on the AC unit to force air through the clogged filters. The result is often a higher than average electricity bill, a damaged fan coil and the risk of allergens like dog dander spreading through the house.


How To Clean The AC Filter


Cleaning the AC filter starts with reading the owner’s manual to acquaint yourself with any machine-specific procedures that may be necessary. Otherwise, on the whole, the following list of generic instructions deliver the best results:


  1. Turn off the AC unit completely. If the unit has its own breaker switch, turn it off there as well. It’s also a good idea to inform the other occupants that it is time for filter cleaning and that they must leave the AC unit turned off.
  2. Remove the filters by following the instructions in the owner’s manual. Make a note of the condition of the filter for future reference.
  3. Vacuum the filter with a low-power vacuum cleaner to remove the most dust, hairs and other gunk. Depending on the type of filter, you may employ a soft brush to loosen packed patches.
  4. Soak the filter in an equal part solution of white vinegar and warm water for about an hour. Gently rinse the filter afterwards. Do not use pressurized water to clean a filter.
  5. Vacuum the location of the filter with a low-power vacuum cleaner to remove any excess dust while the filter is soaking in the cleaning solution. Wipe the area clean with a micro-fiber cloth.
  6. Inspect the clean and thoroughly dry filter for any damage and dirt that cannot be removed. If the filter seems in a good to fair condition, re-install it in the AC unit. Do not be stingy about replacing a filter with a new one because filters are always less expensive than AC units and electric bills.
  7. Switch the AC unit back on and evaluate if there is a perceived difference in operational strength. Should you experience any other issues, it’s advisable to contact your HVAC technician.




It should now be clear that cleaning the AC filter is a necessary task you can perform at least once a month without taking up too much time. Set the schedule down on a calendar. Regular cleaning will prevent the buildup of dust globs that are tough to remove, leading to a decreased lifespan of the filter.


The task of cleaning the AC filter is well within the scope of any handy owner. The replacement of the OEM filter with another type of filter will possibly pose a problem, and owners are encouraged to seek the advice of a professional technician on which replacement filter offers the best fit for their particular AC unit.