Hello, rule of thumb is 20 degrees across the evaporater. This is for a
system that is using the refrigerant designed for it.I think you need a
134a expansion valve. Any valve that you buy is probably a 134a valve.134a
works at as higher pressure. This allows too much refrigerant through the
valve, flooding the evaperator a bit.Not enough evaperation of refrigerant
occurs. Cooling happens with evaperation. Just like sitting beside the
pool. Ahhhhhh