Gage Calibration

Prior to evacuation, check the low-pressure gage for proper calibration and determine if the vacuum pump is operating properly.

With the gage disconnected from the refrigeration system, be sure that the gage needle points to the center of the "0." Tap the gage lightly a few times to be sure the pointer is not sticking. If necessary, calibrate as follows:

1. Remove cover from gage.

2. Holding the gage pointer adjusting screw with one hand, carefully force the pointer in the proper direction to position the pointer at the "0" position. Tap the gage to be sure the pointer is not sticking.

3. Replace the gage cover.