In the air purifier industry, it’s been assumed that less than 20% of people replace their filters as they should, which can dramatically impact effectiveness, as well as allow microscopic particles like mold to grow. In contrast, the Molekule technology, called Photo Electrochemical Oxidation (PECO), destroys pollutants through a catalytic reaction on the filter surface, and changing filters on time will offer peak efficiency. Molekule made sure from the start to make it worry-free for customers to get clean Molekule filters.

Fresh Molekule Pre-Filters and PECO-Filters

Tip: How to change your Molekule filter.

The Molekule dual-phase filtration system

The Molekule air purification process begins with a 360° air intake at the bottom of the device. A powerful fan blows contaminated air upward into the first filtration step, the Pre-Filter. The air then travels up into Molekule’s proprietary PECO-Filter where pollutants are destroyed, and finally exits clean out the top of the device.

Molekule two stage air filtration process

The Molekule air purifier contains two filters in each device: a Pre-Filter and a PECO-Filter.

First phase: Pre-Filter

When contaminated air first passes through the Pre-Filter, very large particles are halted and removed from the air, therefore preventing them from passing further.

Molekule Pre-Filter illustration

Air first passes through the Pre-Filter, where large particles are removed.

Large particles removed by the Pre-Filter typically include:

  • Dust
  • Grains of pollen
  • Strands of pet fur
  • Long fibers from clothing or bedding

You will see this kind of material accumulate over time if you check the Pre-Filter. Like other air purifiers that have a type of pre-filter to protect their primary filter, this accumulation can affect airflow into the unit and reduce cleaning efficiency after a few months.

Second phase: PECO-Filter

After the large particles are removed from the air, any smaller particles that have passed through the Pre-Filter, or have detached from the material it has trapped, will enter the second phase: the PECO-Filter. Many of the tiniest pollutants are the most harmful. They include pollutants like airborne chemicals, ozone, or the allergy-producing proteins on pollen grains and pet dander, which will pass through the Pre-Filter and enter the PECO-Filter, where they are destroyed.

The Molekule PECO-filter, where Photo Electrochemical Oxidation (PECO) takes place.

Some of the pollutants destroyed by the PECO-Filter include:

  • Mold spores
  • Pollen and other allergens like dust mite particles or pet dander
  • Airborne chemicals (volatile organic compounds, or VOCs)
  • Bioaerosols like bacteria and viruses

During the Photo Electrochemical Oxidation (PECO) process, light activates a catalytic reaction to break down pollutants at a molecular level. The PECO-Filter is coated with a proprietary catalyst that react to light inside the unit. The light activates this catalyst, initiating a chemical reaction that converts toxic pollutants into safe substances in the air like carbon dioxide and water vapor.

How dirty filters can affect performance

When carbon-based pollutants are destroyed by the PECO-Filter, they are converted into carbon dioxide, water vapor and other trace gases that float away and become natural components of the atmosphere. Many pollutants are carbon-based, such as VOCs, allergens and disease-causing microbes, and will be broken down into these natural components by the PECO process.

It is also possible that some non-carbon based, solid particles will pass through the Pre-Filter and begin to accumulate as a very fine layer of dust on the PECO-Filter. If you do notice a layer of dust on the PECO-Filter after about 6 months, this may begin to dim some of the light from the top of the device. After this time, you may notice the air is not quite as fresh. We recommend you replace your PECO-filter on time (after 6 months of usage) to maintain peak efficiency.

Role of Pre-Filter

The Pre-Filter ultimately removes large particles and dust from the air, a critical step in the process of cleaning the air in your home. Dust and large particles will accumulate on the Pre-Filter regardless of where you live or how clean you keep your home.


A clean Molekule Pre-Filter vs. a dirty one.

In addition, the Pre-Filter is vital to the Photo Electrochemical Oxidation (PECO) process because it prevents larger particles, which may block the light within the device, from reaching the PECO-Filter.

How frequently should you change your Molekule filters 

To keep your Molekule at peak performance, filters should be replaced on time. Our data indicates what a viable cycle would look like for average conditions, and we recommend the following filter replacement schedule:

  • Replace your Pre-Filter every 3 months to avoid overloading it with large particles
  • Replace your PECO-Filter every 6 months to maintain the highest efficiency

We recommend running your unit 24 hours a day to experience the cleanest air, and the above general schedule is based on this continuous usage time.

Because the Pre-Filter is where large particles are removed from the air, it will become dirty faster and we recommend replacing it every 3 months. The PECO-Filter has a longer lifespan of 6 months; any accumulation of dust on the surface of the PECO-Filter will be much slower because air must first pass through the Pre-Filter.

To make it easy for our customers to receive filter replacements, our auto-refills model is based on this timeline of providing fresh Pre-Filters every 3 months, and a new PECO-Filter every 6 months. The filter life status indicator (found in your Molekule mobile app or the touch screen of your device) can help keep you on track as an additional reminder to replace your filters. The filter status indicator will show a 0% or exclamation mark for each filter when it comes time for replacement. The status indicator counts down from 90 days (3 months) for the Pre-Filter and 180 days (6 months) for the PECO-Filter.

Tip: How to reset your Molekule filter status indicator

You may see visible signs when it is time to change your Pre-Filter. Depending on environmental conditions (some of which are discussed below), you may find the Pre-Filter saturated with dust, pet hair and other larger particles. In this case, we would recommend replacing your Pre-Filter based on these signs.

If you would like to purchase additional filters for your Molekule, please contact the customer support team for help, either through our Help Center request form or by phone at  855-999-9069 (Monday – Sunday : 8am – 5pm PT).

When would your filters need early filter replacement

The presence of pollutants can vary according to your home’s location and conditions, and the filters in your device may require replacement at different rates. The filter replacement schedule above is the best cycle for keeping your unit running at peak efficiency under average conditions.

If you run your Molekule in a place where there is a larger-than-average volume of particles, then you may need to replace your filter sooner.

Some scenarios that may require early filter replacement include:

  • Multiple furry pets in your home
  • A kitchen that is perpetually in use
  • Living near a freeway, parking lot or factory

If you experience these types of scenarios, you can check your Pre-Filter to see if it has become full of particles that are preventing airflow. Sometimes, the particles that block the light on the PECO-Filter will be too small to see, and so a visual inspection is not quite good enough, and it is recommended to change it on schedule instead of delaying replacement. We do not recommend vacuuming or cleaning the Pre-Filter because damage to the filter fibers will make the filter entirely ineffective. Check out our Filter FAQs article here in our Help Center to learn more.

How our filters are constantly improving

The PECO technology has been independently tested and confirmed to destroy pollutants like airborne chemicals, mold, bacteria and viruses. The technology was also put to the test with real people: Our pilot allergy study with participants using the Molekule air purifier in their homes was published in the Journal Allergy & Rhinology. Because the scientific process is very important to us, as a company we continue to develop and further the science behind the technology, and fresh filters that we mail customers incorporate the most recent advancements and technology that science has to offer.


Molekule filter auto-refills

To prevent it from becoming burdensome for Molekule customers to order new filters, we created a filter delivery model so that Molekule filter replacements arrive at your doorstep. These filter auto-refills will ensure you have a fresh PECO-Filter when it comes time to replace it every 6 months, and a fresh Pre-Filter every 3 months. The auto-refill shipments include a set of 2 Pre-Filters and 1 PECO-Filter that will arrive every 6 months, so you will have fresh filters when it comes time to replace them.

Auto-refill shipments include 2 Pre-Filters and 1 PECO-Filter, arriving every 6 months.

Regularly replacing your filters can help prevent your Molekule from running on dirty filters. We encourage you to keep the Molekule technology working at its best with fresh filters to maintain clean air in your home. Our technology is always improving and so are the Molekule filters, ensuring the benefits of clean air for you and your family.

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