The Puraclenz PCO Pre-Filter needs to be replaced or cleaned every 6-12 months depending on the air quality of the installation space. The UV lamp will run for 2.5 years before it will need to be replaced. These time durations assume 24/7 continuous use. The units include indicator lights that automatically notify the user when to replace the lamp or change the Pre-Filter. It is easy to replace the Pre-Filter and Lamp in just a few minutes. There is no other regular maintenance required.