CHARGING OF GAS TO REFRIGERATION UNIT

1.0 PURPOSE:
    
    To describe a  standard operating procedure for charging of gas  to refrigeration unit. 
    
2.0    SCOPE:
    
    The standard operating procedure describes in detail the method  for charging of gas to refrigeration unit.      
    
3.0    RESPONSIBILITY:
    
    The  responsibility  of charging of gas to  refrigeration  unit   lies  with the staff of rank not lower than the junior  utility   operator. 
        
The  responsibility of preparing, reviewing  and approving  the  standard  operating  procedure lies with the  Manager  -  Maintenance,  Head of Production and Head of QAD respectively.
    
4.0    METHOD:
    
4.1        Start the compressor. 

4.2        Close the suction angular valve on the compressor. 

4.3        Open  the suction gauge line flare nut at the  suction  angular  valve of the compressor. 

4.4        Before  charging the gas, check the weight of the cylinder  and ensure that F22 freon gas is present sufficiently in the cylinder.

4.5        Place the cylinder near the compressor in horizontal position. 

4.6        Fix and tighten the flare nut of the gas feeding capillary line  to the cylinder. 

4.7        Fix  the  flare  nut of the gas feeding capillay  line  to  the  suction angular valve of the compressor.

4.8        Slightly release the gas from the cylinder and loosen the flare  nut  of  the suction angular valve till the  gas comes  out  by  which we can eliminate the entry of air into the system.

4.9        Tighten the suction angular valve capillary flare nut. 

4.10       Open the angular valve by 3 - 4 turns. 

4.11       Open  the cylinder valve by 5 to 6 turns and observe  the  discharge pressure gauge.

4.12       Let the discharge pressure gauge raise by 5 PSI  more than  the  earlier  pressure. If the discharge pressure is  exceeding  260   PSI stop charging the compressor by closing the cylinder valve.

4.13       Tighten the cylinder valve and close the suction angular valve.

4.14      Remove the flare nut and disconnect the charging pipe line from  the suction angular  valve.

4.15       Connect  the suction gauge line and slightly open  the  suction  angular valve and observe the suction gauge.

4.16      Leak  test  should be done immediately.  If any leak  is  found  rectify  the leak and ensure that the gas pressure is 15  -  25  PSI and 35 - 50 PSI at 0 degree C and +15 degree C respectively  for brine and  chilled refrigeration units respectively.

4.17       If the  pressure  is  low repeat steps 4.1 to 4.16.

4.18       After completion of charging the gas weigh the cylinder and put  a gross weight tag to the cylinder.   

5.0        RECORDING:

    Nil. 
    

Refrigeration unit, engineering, refrigeration unit