Probable Cause:
The external equalizer line supplies the evaporator’s outlet pressure to the underside of the TEV diaphragm to close the valve. If the external equalizer line is plugged or capped, the valve will most likely be wide open, causing a flooding condition. In some rare occasions however, internal valve leakage via push rods could cause a constant pressure in the underside of the diaphragm, which would cause a high superheat.
Remedy:
If the external equalizer is plugged or capped, repair or replace to insure an unobstructed pressure flow