Too small line set?

I recently had condenser and air handler straight cooling ac system changed out with a Rheem 4ton set by a local contractor. The installer failed to change the line set and used the existing set, which is only 1/2" x 3/8". Install manual specifies a 7/8" x 3/8". Line set is 25' long 8' lift, in SW Florida.
What problems will result?

source https://hvac-talk.com/vbb/showthread.php?2227057-Too-small-line-set&goto=newpost