The supply temp inside the trunk duct about 3 feet after the coil sometimes drops as low as 41 degrees.
So far I have seen no indication of the E-coil freezing.
Some Background: In April 2008 a new trane XL15i 4-ton Ac was installed in my home along with a 5 ton ADP coil and a 100k btu XV95 furnace for a 2800 square foot home in central NJ.
The system was greatly oversized for my ductwork and my ESP started at 1.2. Modifications to solve the high esp issue included adding a helper duct for the supply, increasing my return drop from 24x10 to 25x20, switching from a 1 inch restrictive filter to a 5 inch media filter, and lowering my blower speed ultimately down from 400 cfm/ton to 280/cfm/ton. These changes appear on the surface to have solved all my problems including a high humidity issue that I had. The house is now quite comfortable and the ESP is down from 1.2 to 0.57. The reality is I probally could have gotten away with a 3 ton system but I knew nothing about proper sizing at the time.
My current question:
1. Since my initial refrigerent charge (410) was not adjusted are there potential issues?
2. My supply temp right after the coil gets down to 41F while the return air is 70. Does this suggest a potential issue? I've read that a 20 degree delta is as good as one should expect under normal conditions