Johnny,
There is a problem with the return and supply duct. The infinity and evolution systems are the only ones that actually look for static pressure so now you know you you may have always had this problem. Unless it's filter or trash that is blocking air flow.

What do you mean by floor opening? Is the furnace sitting on the floor over a return duct opening? Is there a clear passage way of the return air? The 14 x 20 what is the depth? does it make a sharp turn 90? Take off the blower door cover and run a static test see what you have.

What type of filter are you using and you are not double filtering are you?

I would be checking the supply duct and the return duct

For the supply duct is it a long run? does it have many 90 in the trunk line? I would make some opening in the supply duct as close to the furnace just to check static pressure.

Also hopefully there is nothing blocking air flow in the evaporator coil.

No get up there soldier and let's get some answers! :-)

Oh and thank you for your service!!

Hey thanks for the thanks! I loved everyday of it and I volunteered for it all, best choice I ever made.

Ok. the situation of the opening on the bottom. The unit sits on a hollow wooden box located in the garage. The box is 19 inches High, and its 37 inches wide and 36 inches deep. The return louver is located in the house but does not contain the filter. I removed that louver as stated above and the static pressure tests were the same. The opening I was referring to is the opening in the top of the box, leading to the filter and the bottom of the unit. The bottom of the unit is 21 x 30, the filter is 20 x 25, and the actual opening that allows air flow to the bottom of the unit is 14 x 20. The manual says that opening should be 19 3/8 x 24 1/8, and I was wondering if that measurement was an issue that could cause that static pressure to be so high.

I am using a media type filter and I am not double filtering.

There are probably three 90s in the supply piping, and its flex type ducting, it goes all the way to the attic on the second floor and then is distributed to the 3 bedrooms located on the second floor. The downstairs gets some serious airflow. I am guessing on the ducting turns because I would have to rip out a lot of drywall to actually see it.

The evaporator coil is brand new and came with the new furnace and condenser.

I am still working with the installer on this and plan to meet with him on Friday, but I like to have the upper hand on knowledge when I'm dealing with them.

Thanks again for all the previous comments, and I look forward to your advice.

Thanks Johnny P