I've resurrected this old thread because it has information I was searching for but didn't exactly find. I have an Infinity MVP58-80 and am confused by the autosense dirty filter feature. Here's what I got for readings with the old filter, no filter, and a brand new filter. CFM is 1450 in all cases with the fan on high.

Old filter. 1068 RPM .76 static

No filter at all. 1038 RPM .69 static

Brand new filter. 1047 RPM .71 static.

All of this makes sense and looks more or less okay except the control is saying the filter is 100% used despite it being brand new. I have some of my registers closed (all but one in the basement and an entryway upstairs. In the summer it is 76F upstairs and 70F in the basement so I don't see the need to open those registers at all. Am I causing the problem by doing this?

Jon