Low pressure switch erratic in operation
a. Check tubing to switch to see all if clogged or crimped.
b. proper setting of switch.
Insufficient refrigerant in system - Add refrigerant
Suction service valve closed - Open valve
Insufficient water flowing through condenser or clogged condenser.
a. Adjust water regulating valve to condenser.
b. Clean condenser.
Discharge service valve not fully open - Open valve
Air in system - Purge