When a System Becomes Contaminated

TM 10-4110-262-13&P

0031 00

NOTE

Replace oil with new fresh oil taken from a sealed container only.

NOTE

Change the dehydrator if the oil is contaminated.

When a System Becomes Contaminated

A severely contaminated system may be indicated by black oil in the compressor. If severe contamination

occurs, it will be necessary to flush the complete system. If flushing is required, use industry approved

materials.

In all cases when this occurs you must determine the extent of contamination. Do this by removing the

dehydrator and determine if the darker colored oil is present at that point of the system. If it is, flushing the

system is recommended.

If the oil appears clean at the dehydrator, install a new dehydrator and replace the compressor with clean

new oil. Refer to checking and draining the compressor oil section for details.

System Cleanup

1. Recover the refrigerant.

2. Remove the suction pressure regulator and install a temporary suction line cleanup filter.

3. Change the compressor oil as described in this WP.

4. Change the expansion valve nozzle.

5. Change the dehydrator as described in WP 0037 00.

6. Leak check, evacuate, and charge the system.

7. Run the unit for at least six hours.

8. Acid test the oil.

9. If the acid test fails, change the dehydrator, and begin process starting from Step 3.

10. If the acid test passes, perform low-side pump down (as described previously in this work package).

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