My geothermal takes 28x30x2 merv 11 filter. I had bought some online a couple years ago but the company no longer is around. I have searched for the filters online and come up with brands I have never heard of. Any brands that are recommended are not in the size I need. Are the filters that I find on Amazon any good?
I get mine from brookaire dot com. Look under residential, geothermal, geothermal by size. They have 28x30x2.
Mine takes 32x30x2, which are very difficult to find. However I just order in 16x30x2, which are much easier (and cheaper to ship) and tape them together. So if you have trouble finding 28x30x2 from a supplier, consider 14x30x2. I'm in Canada, so my supplier recommendations would probably be of little value to you.