Code 93 (Low Pressure Cutout or LPCO). If refrigerant pressure is abnormally low (2 psig +/- 2) the normally closed switch contacts will open to signal the Controller. It removes power from the compressor clutch. Check refrigerant in the system.
Code 10 (High Discharge Pressure or HPCO). If the refrigerant pressure becomes abnormally high (400 psig) the normally closed switch contacts will open to signal the Controller. It removes power from the
compressor clutch. When refrigerant pressure returns to normal the normally closed HPCO contacts will close. If cooling is still required power is applied to the compressor clutch and starts the compressor.
Code 19 (Low Engine Oil Pressure or Oil Pressure). This normally closed switch opens when oil pressure rises above 15 psi. The switch itself may be bad.
See a list of Codes for TriPac Evolution (2nd generation).