This is where less gold-plated products may be better! Look at page 6 here: https://leesheatingandcoolingservice.com/wp-content/uploads/2019/03/aprilaire-all-

This is where less gold-plated products may be better! Look at page 6 here: https://leesheatingandcoolingservice.com/wp-content/uploads/2019/03/aprilaire-all-products-specification-reference-guide-2210.pdf https://leesheatingandcoolingservice.com/wp-content/uploads/... The 216 filter has 0.17" wc of initial pressure drop at 1000 cfm as compared to 0.12" wc for its MERV 13 equivalent, the 213. You can just swap it in if you started out with MERV 13 [0] have 0.05" wc of extra pressure budget (and an existing compatible housing), and you can probably save 0.05" wc by just changing your filter more often. Or you can design something like this into a new system, just like you would have to design a Perfect 16 in. [0] You must have some kind of return air filter to avoid destroying your fan coil. MERV 13 is somewhat of a baseline for a decent system.