> Check oil level in the compressor.
> Open the condenser cooling valves, close the drain cock and start cooling water pump
> Open all the refrigeration system valves except the compressor suction valve. ensure that compressor discharge is open .
> Start Blower and put the solenoid valve in auto
> check power supply to the compressor and solenoid valves.
> Now open the suction valve of the compressor and start the compressor.
> observe the system for any abnormal operation for ten minutes before putting it in “auto-mode”
> The system generally operates automatically once started. If the temp., in the room rises, solenoid valve opens and the refrigerant then flows through the evaporator through the expansion valve. As the refrigerant flows through the evaporator, compressor suction pressure begins to rise. This suction pressure is sensed by the “lpco” which cuts-in at it’s high pressure setting and starts the compressor.
> When the intended cold temp., is reached, the thermostat closes the solenoid valve.
> Compressor continue running, unloading the cylinders until the suction pressure is low enough to actuate low pressure cut off (LPCO). When set pressure is reached the “lpco” switch stops the compressor.
Stopping
> Refrigeration plan cut in and cut off automatically here below the procedure for manual stopping
> Close the discharge valve of the condenser.
> When the compressor suction pressure below set point compressor will be cut off by low pressure cut off
> When the compressor suction side pressure come up it will run for some time and cut off let it do the same process 2 time and allow whole refrigerant in condenser
> Close the suction and discharge valve of compressor
> Switch off the breaker.