I’ve bought many brands of ac filters for decades and never had the support webbing of the filter on the upstream side of the filter (according to air flow direction arrow). I don’t know whether to trust my decades worth of experience or trust the air flow direction arrow.
Response from filtrete.comBy Filtrete Brand, Social Care, September 8, 2020
Hello – Thank you for taking the time to leave your review. We are sorry to hear of the confusion. In the past we have used metal mesh supports on the downstream side of our filters. We have designed a new polypropylene support material for these filters which supports the filter material from the upstream side. Please install the filter according to the air flow arrows. If you have any additional questions or concerns, please connect with us directly at 1-800-388-3458 M-F 8am-5pm CT.
[This review was collected as part of a promotion.] I got this 4 months ago and ready to change it again, only problem I have is I need 6 for my house!
[This review was collected as part of a promotion.] We have a furnace that uses the 16x25x4 size allergen filter, and we keep either the heat or the air on all year because of my allergies--no open windows, doctor's orders. I've noticed that there is very little dust on my furniture since using the Allergen Defense filter, which lasts for a year, and I have little or no allergy symptoms indoors. It helps me breathe easier!