Water is not a good idea especially from a house system a lot of impurities
that might get left behind. Use a A/C flush on condenser and evaporator and
all hoses.  After the flush you must replace the A/C oil in the system drain
oil from the compressor  (divide total oil and put in evap, condenser,
compressor and lines)  put new dryer if system has been opened for a long
time  reconnect system and draw a vacuum for min 1 hour as the system is
large. fill system and retest. ( make sure your rad fan is working when
system is running)