The original filter designs for the AirDoctor 3000 and 5000 units will not fit in the new AirDoctor 3500 and 5500 units, however, the new AirDoctor 3500 replacement filters WILL fit in both the AirDoctor 3000 & 3500 and the AirDoctor 5500 filters WILL fit in both the AirDoctor 5000 & 5500 units.
We are patenting our unique design to ensure that our customers are purchasing genuine, tested, and verified AirDoctor replacement filters. We have purchased and tested knockoff replacement filters that claim to meet the performance of ours. None of them match AirDoctor specifications, and the majority fail to meet the minimum HEPA standard, while others impede airflow to the extent that they will damage the AirDoctor motor.
The new filter is designed to fit in existing AirDoctor Purifiers as well as future models of the AirDoctor. Many customers have placed the previous filter incorrectly in their AirDoctor, and this new design eliminates the chances of anyone placing a filter backward in their AirDoctor. It will help ensure that customers are protecting their units and receiving the utmost benefit from their AirDoctors.