Recommended replacement schedule: every 5-7 years (depending on air quality and frequency of use).
Please note: If your AllerAir unit was purchased before November 2001, you must replace the Carbon filter at the same time as the HEPA filter. The Carbon filter is now larger (2.5" instead of 2"), which means the HEPA filter also had to be re-sized to accommodate this change.
Please note: These items are made to order and are non-returnable. Please allow 2-4 weeks for delivery.