Quote Originally Posted by kenengineering
...what is the optimum SH is for a given system...?
See below...

Quote Originally Posted by me
The evaporator manufacturer should have designed the evaporator to provide the required cooling capacity at a specific superheat. That is the number you want.
A close coupled system (meaning very short piping runs) should have about 10 degrees (F) of evaporator superheat.

If the system has a stable operation (On or OFF) and no capacity control this should be OK. A couple of degrees one way or the other is not a big deal, but you should be able to nail it down if the system is stable.