A good A/C shop should be able to figure it out, pretty simple system. Hopefully they put a vacuum on the system before they filled it after replacing the compressor. Standard temp/refrigerant pressure tables apply as the manual only calls for a liquid fill by weight so start with system pressure to begin with. If that doesn't work you may need a complete evacuation and refill, couldn't hurt to install a new receiver/drier/filter while you're in there if it was opened for long.