The 91-011 is the 17 1/2 inch x 17 1/2 inch x 12 inch replacement HEPA filter for the Ultravation HEPA Whole House Air Cleaner 93-002. The 91-011 is also the replacement HEPA filter for the Ultravation Photronic Multistage Air Cleaner with true HEPA filtration models: 92-019, 92-020, 92-021 and 92-023.

The Ultravation 91-011 Replacement HEPA filter media combines state of the art mini-pleat construction techniques with superior reliability to deliver maximum value. The HEPA filter media is manufactured with high efficiency glass microfiber media that is 99.97% efficient, when tested with .3 micron-size particles. The HEPA microfiber media is randomly tested and certified to meet minimum efficiency requirements. The media pack consists of a continuous sheet of the pleated glass microfiber that is moisture resistant and does not support the growth of bacteria or mold.

The manufacturer states that if you change your pre-filter regularly the HEPA filter can last as long as 5 years. We recommend that you change your HEPA filter every 3 to 5 years under normal operating conditions.