Honeywell Home F100F2025 filter size

The F100F2025 is the 20 x 25 inch model in the Honeywell Home F100 line of media air cleaners, made by Resideo. It is a cabinet with an access door and a MERV 11 pleated media filter, and it mounts in the return air duct of a gas, oil, or electric forced air furnace. An earlier revision of the installation guide lists the 20 x 25 F100 as F100F2010.

The replacement filter table in installation guide 68-0239EF pairs the 20 x 25 size with part FC100A1037 (MERV 11) or FC200E1037 (MERV 13). Resideo's product page lists the FC100A1037 at 19.94 by 24.88 by 4.38 inches, and the earlier guide gives it as 20 x 24-7/8 x 4-3/8 inches. That 4.38 inch depth is deeper than the 4 in a nominal 20x25x4, so check the depth your cabinet needs before buying a generic filter.

The guide says to replace the filter every six months, before heating season and before cooling season, and at least once per year. It also says the media must be replaced when the pressure drop across it reaches 0.5 in. w.c., and that an atomizing humidifier or combined heating and cooling can call for more frequent changes.