Fujitsu AOU48rlfxz problem in heating,need help from brothe's.........

[ajhvacny]

hi ,i just in to this forum, i had the problem in Fujitsu Aou48 in heating mode the outdoor fan coil icy up in them 34F raining night. the defrost start 6min. however the next day them was 40f no icy the defrost also proceed ........is that the outdoor sensor got problem, the unit should be running until the lowest 5 f why it happen in 40f???
thank you........for helping

[Mr.Ductless]

Your charge is off most likely, have you calculated your additional charge usign fujitsus onlie calculator? Remember these units do not come precharged for piping.