1. Exhaust the refrigerant
A.Connect the compressor with pressure meter.
B.Open the valves of high and low pressure gauge, the refrigerant will exhaust automatically. (pic 1)C.The refrigerant will be all out of the compressor when the needle of gauges points ‘0’. (pic 2)
2.Remove the compressor
A.Remove three copper pipes with blow torch. (pic 3)
B.Remove screws of the base. (pic 4)
Then the old compressor can be taken out.
3.Load a new compressor
A.Fasten the base with screws. (pic 4)
B.Connect three pipes with welding copper. (pic 5)
Note: the pipes must be welded very carefully to make sure there’s no leakage.
4.Check leakage after installation
A.Put nitrogen into compressor, to check if the leakage exists. (pic 6)
B.Connect the pipe to low pressure entrance, then add nitrogen into it slowly (pic7)
C.Stop adding nitrogen when the gauge shows to 300psi. (pic8)
After that, keep the compressor for 24 hours for stability.
D.After 24 hours, check if the meter stays at 290psi-300psi. If yes, there’s no leakage. (pic9)
If not, please check if the pipes are connecting well, welding them again.
Then repeat step C, D. (pic 5)
Extra nitrogen after the compressor is confirmed no leakage:
E.Extra the nitrogen from low pressure inlet and high pressure inlet. (pic 10)
F.When the meter shows 0, the nitrogen is totally out of compressor. (pic 11)
5.Vacuumize the compressor
A.Connect the pipes: (pic 12)
B.Open two valves of gauges, turn on vacuum pump. (pic 13)
C.Turn off the pump when the value is under minus pressure. (pic 14)
D.Close valves of high and low compressor. Keep this state for 30 minutes
6.Add the refrigerant
A.Take the yellow pipe off the pump, and connect it with refrigerant box, and open the valve. (pic 15)
B.Make sure high pressure valve is closed. (red one) Turn on low pressure valve on.(blue one) (pic16)
C.Tight the blue valve a little to slow down the refrigerant speed when the needle reaches to 2 bar. (pic17)
If adding refrigerant too fast, the valve might be broken and cause the compressor broken again.
D.When the needles of red and blue valve all reach to 10 bar, it means the refrigerant is enough.
E.Close the blue valve, then finish the process, now you can make the test chamber run at -40C.
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