Return Grille Filters and Airflow??

[gman06]

I recently had a new 5 ton system installed. It's a Rheem RARL060JEC with a RHPNHM6024 handler.

The installer noted that my cut-it-yourself blue filters at the return may not be the best option. I have 2 returns that I thought were 20x20. But it turns out they are 19.5x19.5x1, so it looks like I'll need to custom order something.

The question is what filter to go with that won't unreasonably restrict the airflow. It sounds like either a polydisposable or pleated disposable (monthly) would be best. I'd appreciate any suggestons on the best path to take. If I special order 19.5x19.5x1, what airflow pressure should I look for?

[FrankD]

I bet the standard 20x20x1 at the store will work. The size you see on the filter is the "Nominal" size. The actual size is usually a little smaller. Just as a wood stud 2x4 is really 1.5 x 3.5. This threw me at first too.

[beenthere]

Few air filters are the size they are marked.

Most 20x20 are not 20"

[gman06]

Well I gave it a try. I bought a standard 20x20x1 at Lowe's. No go. You are right, as it is marked with actually being 19 5/8 per side. Unofrtunately, it didn't fit. I need another 1/2 inch per side. I went back and looked for a 19x19x1, but they didn't have them. Guess I'm back to custom. Any suggestions of which one based on the system?

[beenthere]

You can ask your local HVAC contractor to order you a case of air filters the size(tell him the actual size) you need.

It really doesn't cost that much for special orders.

[freeflow]

Your installer may be able to change the return grills to a standard size with a small amount of work and then you could pick up filters that will fit at almost any store thats convenient for you.

[FrankD]

Are you sure of the original size? I looked at the site where I bought my filters from, and it says the actual size of the 20x20x2 is 19-1/2" x 19-1/2" x 1-3/4.

[dash]

Have a Pro test the static of the duct system,before buying any filter that is above a standard throw away!

[ACFIXR]

Your installer may be able to change the return grills to a standard size with a small amount of work and then you could pick up filters that will fit at almost any store thats convenient for you.

your grills are a little on the small side anyway, upsize to 20x25 if possible.