How to Clean an Air Purifier Filter – ( Ultimate 2022 Guide )

Air purifiers significantly improve air quality by removing dust, dander, germs, and various air pollutants. The air purifiers have various filters installed in them that block various pollutants at different stages.

For optimum performance, your air purifier must be working properly. Therefore the maintenance and cleaning of air purifiers are crucial. Since filters of an air purifier have a limited life, they need to be replaced or cleaned occasionally.

Over time, these filters get clogged, become sticky, and often stop working. If you’re going to purchase a new air purifier or have already installed the one, you must need to know how to clean it as well:

How to Clean an Air Purifier Filter?

Various types of air filters are used in air purifiers. They work in combination with each other. Each filter has its own speciality to deal with a specific type of pollutants. Therefore each filter has its own cleaning requirements.

Here is a complete guide on “how to clean air purifier filters?”

1. Ionic Air Filters

Ionic air filters generate static electrical charges that attract and grab air pollutants as they pass through the filter. These filters are usually metal plates on which air pollutants stick.

Over time, they stop functioning, as a lot of air pollutants are collected on these plates. These filters are washable and need to be cleaned once a month if you want to get the best out of them.

To clean the ionic air purifier filter, follow these steps:

  • Switch off and unplug the air purifier
  • Usually, these filters are installed as sliding plates, and they easily slide outside. However, it is not the case with every appliance. If they are not slideable, you should follow the manufacturer’s instructions to take the filter out for cleaning purposes.
  • Since these filters are washable, put them in the sink and bathtub under running tap water
  • Use a scrub, or brush to remove the collected debris from the plates
  • Always be gentle on the plates and do not apply force to clean the filter
  • Wait until the plate is completely dried as inserting a wet filter can damage the whole system
  • Slide the filter back into the air purifier
  • It is advised to monitor the filter condition regularly

2. Pre-filters

Pre-filters are usually at the first stage of an air purifier’s filtration system. They are designed to catch the large visible particles, like hair, pieces of cloth and paper, large dust particles, pieces of leaves and straws, etc.

These filters block these particles at the first stage so that they may not enter and damage the internal parts, and sensitive filters like HEPA filters inside the air purifier. In this way, they extend the life of true HEPA filters also.

Over time, these filters get clogged and can disturb the whole cycle by blocking the air also. You need to monitor the condition of these filters regularly. Some air purifiers have also filter indicator lights, telling you if you need to clean or replace the filter. Air purifiers also produce a specific noise when a sufficient amount of debris is collected in the pre-filters.

Follow these steps to clean the per-filter of air-purifier

  • Disconnect the appliance from the electrical supply
  • Remove the pre-filter according to the instructions provided by the manufacturer
  • Never apply force to remove the filter. Some filters are screwed to the appliance, while others use the clips and knobs
  • Clean the filter with a dry cloth and to remove the large particles
  • Place the filter under running water
  • You can use soap or detergent to clean the filter
  • Gently use the brush or scrub to scrape off the sticky materials from the filter.
  • Wait until the filter is completely dried

Remember that you should also clean the pre-filters daily. You can use a vacuum cleaner with gentle pressure to remove the dust and debris from the filters.

Never use a wet cloth to cleanse the inner side of the pre-filter. Moisture makes the surface more sticky and potentially damage the internal parts of the air purifier.

3. HEPA filters

HEPA filters are specialized filters that remove the particulate matter and smaller size pollutants. Some filters can remove particles as small as 0.2 microns.

These filters remove allergens, pet dander, pollens, and fine particulates. These filters significantly improve air quality. Therefore, air purifiers with HEPA filters are recommended for people with weak immune systems, asthma, or allergies.

Generally, these filters have a life of around six months. After six months, you either need to clean or replace the filters. It is also important to replace or clean the filters because it may be a favourite place for molds to grow.

These molds become part of the air cycle and are released back into the environment. More than 90% of HEPA filters are not washable and cleanable, and you need to replace them every six months.

However, filter replacement is a costly process, and most of the users still have to clean the filters at least once. But these filters are highly sensitive and delicate structures; you need to be extremely careful.

Moreover, some HEPA filters are washable, but they are found rarely. HEPA filters are made of plastic or fibreglass. It comes in fibre mesh, made of very fine fibres.

Follow these steps to clean the washable or permanent HEPA filter of an air purifier

Switch off and unplug the appliance

  • Remove the HEPA filters, according to the instructions provided in the user’s manual
  • To remove the accumulated dust and debris, use a vacuum
  • Always use a handheld vacuum because it gives you more control and prevents any accidental contact with the filters
  • Use a soft brush attachment or nozzle of small size with the vacuum
  • Never push the  brush or nozzle inside the filter; it can severely damage the fibres of the filter
  • Use low pressure, and be very gentle during the whole process to minimize the damage

If your air purifier contains a washable HEPA filter, follow these steps

  • Soak the filter in lukewarm or cold water containing soap or detergent
  • Do not use a brush or any other material to rub the filter
  • Do not apply any force to remove the dust and debris
  • Rinse the filter under the gentle water flow
  • Carefully place the filter on a clean, dry surface and wait until it is completely dry

4. Charcoal or Activated Carbon Filters

Charcoal filters remove a variety of air pollutants. They absorb organic pollutants, foul smells, and fumes and release the fresh and clean air back into the environment. There are two types of charcoal filters: wet carbon filters and dry carbon filters. Wet filters are washable, while dry filters can be vacuumed.

Follow these steps to clean charcoal or activated carbon filter of an air purifier

  • Unplug the air purifier
  • Remove the filters by following the guidelines provided in the user’s manual
  • If it is a dry filter, use a dry piece of cloth and gently whip off the accumulated dust
  • Use the vacuum in low suction settings
  • Gently vacuum the whole surface
  • If it has multiple surfaces makes sure you clean all of them
  • If it is a wet charcoal filter, soak it in lukewarm/cold soapy water
  • Use a soft brush, or gently scrub with hands to remove the contaminants
  • Rinse under low-pressure water
  • Wait until the filter is completely dry

For optimum air purifier performance, you need to clean the filters after every 3 to 4 months. These are some general guidelines you should follow before cleaning the filters of an air purifier

Do not use high-pressure water as it can damage the filters.

  • As air purifier filters contain significant amounts of harmful air pollutants, it is advised to perform the cleaning process outside a home
  • It would help if you chose a place where air quality is less important, like a basement, garage, or gallery
  • Always wear a protective face mask and gloves
  • If you are asthma or allergy patient, you should not become part of the process
  • Use a plastic bag to collect the dust and debris
  • Cover the floor with a plastic sheet
  • Dispose of the debris at proper place
  • Use soapy, lukewarm, or cold water according to the guidelines provided in the user’s manual
  • Do not wash the filters that are not washable; if you do so, it will be ruined

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Can you wash and reuse air purifier filters?

Some filters are washable and reusable, while some are not. Usually, charcoal filters and pre-filters can be washed and reused, but HEPA filters need to be replaced.

How long do filters last in air purifiers?

Usually, filters need to be cleaned or replaced twice a year. However, it also depends upon the quality of air. If air is highly saturated with contaminants, it may reduce the filter’s life, and you may need to clean or replace filters after every 3-4 months.

Is a HEPA filter washable?

Most HEPA filters are not washable. However, some advanced air purifiers contain washable HEPA filters.

How do I know if my HEPA filter is dirty?

Some air purifiers have a filter indicator light that turns red when the filter is dirty. Some fir purifiers have filter alarms that only ring when the filter is dirty. However, some filters produce unusual noise when the filter is dirty. You can also feel the difference in air quality when filters are not working properly.