Good morning, first of all to make a good diagnosis, it is essential to measure the working pressure, as it is original you must use a pinch valve and with it you click the pipe and you get the reading of the operating pressure, when disconnecting the forcer from the condenser what you are doing is increasing the working pressures, both high and low, and as the evaporator begins to freeze, I presume that the working pressure while the forcer is on is empty, which occurs when there is either a refrigerant leak or internal obstruction in filter drier and / or capillary tube.