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How to Maintain HEPA Air Purifiers?

Each HEPA air purifier model comes with different features and specifications, but also with different maintenance requirements.

But in general, in order for HEPA air purifiers to function properly, their air filters must be in top condition and air pathways must be clean.

Published: March 3, 2021.

HEPA Air Purifier Maintenance

germguardian ac5900wca mHEPA air purifiers must be kept clean, regardless if they are small desktop units, or large, high-capacity units.

Common maintenance tasks include:

- replacing the UV light bulb,

- cleaning the air pathways,

- cleaning the sensors,

- cleaning and replacing the air filters.

Note: For exact maintenance procedures, be sure to read the manual of the device which You have. And always be sure to turn the unit off and unplug it from the power socket.

UV Light Bulb

UV Light Bulb, if present, is used to sanitize purified air and in combination with Titanium Dioxide (TiO2) to decompose Volatile Organic Compounds (VOCs), smells, odors, and other compounds that have managed to pass through the air filters.

lb4000 uvc bulb

UV light bulb is replaced periodically, depending on the number of hours it has been used - turn off the unit, unplug it from the wall, and by following the instructions in the Owner's Guide disassemble the unit and replace the UV light bulb.

Assemble the unit (as instructed), test it and that is all - the new UV light bulb will operate more efficiently and more thoroughly.

 Air Pathways

Keeping the unit generally clean includes cleaning the air pathways inside the unit, cleaning the body of the air purifier, and keeping the area around the air purifier as clean as possible.

So, take the dry or slightly moist cloth and wipe the unit thoroughly. Then, open the unit, remove the air filter (as instructed in the Owner's Guide) and wipe all the surfaces, even if they look clean.

Assemble the unit and test it.

Cleaning the Sensors

Not all air purifiers come with air quality sensors, but those that do come, depend on such sensors heavily when operating in Auto Modes.

Sensors are most often cleaned using dry cloth as instructed in Owner's Guide - turn the air purifier off, unplug it from the wall, locate sensors and if required remove protective cover(s).

Clean the sensors gently and assemble the protective cover(s) - if present.

Turn the unit on and test in Auto Mode.

Cleaning and Replacing the Air Filters

Cleaning and replacing the air filters are the most important air purifier maintenance tasks - if the air filters are dirty, air purifier efficiency is decreased and air purification level is questionable, to say the least.

Air filters are generally replaced every 6-12 months, depending on the unit's use, but also conditions where they operate - people with health issues, with kids and pets should check their air filters more often and if required clean and even replace them more often.

It is a good practice to check the air filters every 2-4 weeks - turn off the unit, unplug it from the wall and remove the filters' protective cover and inspect the air filter. air purifier maintenance 1

As one can see, this air purifier was left uncleaned for too long (but less than 6-7 weeks!).

Note: some air purifiers come with air filters that can be washed - mostly air pre-filters, while HEPA and activated carbon air filters can be cleaned (for example, gently vacuumed), but cannot be washed.

air purifier maintenance 2

This second photo shows just how much dirt can accumulate on the surface of air purifiers' air filters - just one pass of the dusting brush (suction strength decreased in order to prevent any damage to the air filter assembly) shows how the air filter is dirty!

Now, using a dusting brush and low suction mode gently vacuum the air filter. The difference is huge:

air purifier maintenance 3

Now, take the slightly damp cloth and wipe the rest of the unit.

Assemble the unit, plug it into the wall socket and test it.

Note: if You have an air purifier with the washable air filter(s) be sure to thoroughly air dry the air filters before assembling them back into the unit.

After some time air filter(s) must be replaced since the amount of tiny particles deeply embedded in the air filter increases, decreasing the air filter efficiency and the ability to capture small particles.

Note: when purchasing the new air filters, always go for OEM air filters - air purifiers operation depends on the quality of the air filters, and cheap, low-quality air filters decrease the ability of air purifiers to clean the air.


Long Story Short: Air purifiers are often used as set-and-forget devices, but for them to function properly, some maintenance is required.

Check your air purifier(s) every 2-4 weeks and keep it clean - such units will operate longer and do their task properly.






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