PURGING THE REFRIGERANT R-22 SYSTEM - TM-9-4120-423-14-P0331

TM9 4120-423-14&P

Open the nitrogen cylinder valve and adjust the regulator so that less than 1 - 2 cfm (0.028 -

0.057 cubic meters/minute) of nitrogen flows through the system.

Check discharge from hose attached to the low pressure charging valve to be sure that no oil is

being forced out of the system.

Allow nitrogen to sweep through the system at the rate of less than 1 - 2 cfm (0.028 - 0.057 cubic

meters/minute) for a minimum of 5 minutes, before starting any brazing operation. Then allow it

to continue to flow at the same rate until all brazing operations are completed.

After installation brazing operations are completed, allow nitrogen to flow for a minimum of 5

minutes.

Close nitrogen cylinder valve, nitrogen regulator, charging manifold valve, and both high and

low pressure service valves on the unit.

Disconnect the hose from the nitrogen tank.

Make sure all repairs are completed. Go to WP0072.

END OF TASK

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