163.Reefer compressor oil charging

PROCEDURE FOR ADDING OIL TO A COMPRESSOR

Adding oil to a compressor is often required, and the operator should be familiar with the different procedures used. There are 3 procedures used, depending on the type of system encountered and the type of tools at hand. These procedures are: (1) the open system method, (2) the closed system method, and (3) the oil pump method.

Open system method, use the following procedure:

1.    Connect the gauge manifold to the system service valves. See figure.

2.    Close the gauge manifold hand valves and open the compressor service valves.

3.    Start the unit.

4.    Front-seat the compressor suction service valve and run the unit until the low side pressure is reduced to 1 or 2 psig (6.9 kNm² or 13.8 kNm²). The low pressure switch may need to be bypassed.

5.    Stop the compressor.

6.    Front-seat the compressor discharge service valve.

7.    Open the low side hand valve on the gauge manifold and relieve the slight pressure remaining in the system.

8.    Remove the oil fill plug and pour the oil into the compressor crankcase until the proper level is reached. Use precaution to prevent contamination of the oil. 

9.    Close the low side hand valve on the gauge manifold.

10.  Slightly open the compressor suction service valve and allow a small amount of refrigerant to escape out of the oil fill hole.

11.  Close off the compressor suction service valve.

12.  Replace the oil fill plug and tighten.

13.  Back-seat the compressor service valves.

14.  Start the compressor and check the oil level in the compressor.

15.  Remove the gauge manifold from the system.

Closed system method, use the following procedure:

1.    Connect the gauge manifold to the system service valves.

2.    Place the c enter charging line in a container of clean dry oil. See Figure.

3.    Open the system service valves until a pressure is indicated on the gauges.

4.    Slightly open the low side hand valve on the gauge manifold and purge a small amount of refrigerant through the lines and oil.

5.    Front seat the system service valve.

6.    Start the unit and draw a vacuum on the compressor crankcase.

7.    Open the low side hand valve on the gauge manifold and draw the oil into the compressor through the service valve. Be sure that the center line remains in the oil to prevent air entering the system.

8.    When a sufficient amount of oil has been drawn into the compressor, close the hand valve on the gauge manifold.

9.    Back-seat the system service valve, and place the unit in normal operation.

Oil pump method, use the following procedure:

1.    Connect the low side gauge of the gauge manifold to the system suction service valve.

2.    Close the low side hand valve on the gauge manifold.

3.    Crack the system service valve until a pressure is indicated on the gauge.

4.    Connect the center charging line to the oil pump. Do not tighten the connection.

5.    Open the low side gauge manifold hand valve and purge refrigerant through the loose connection for a few seconds, then tighten the connection.

6.    Place the oil pump in a container of clean dry oil.

7.    Open the gauge manifold hand valve completely.

8.    Move the system service valve to the midway position.

9.    Pump oil into the system until a proper level is reached. See figure

10.  Back-seat the system service valve.

11.  Close the low side hand valve on the gauge manifold.

12.  Remove the gauge manifold and place the system in normal operation.