Gage Calibration

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

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

1. Remove the cover from the gage.

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

3. Replace the gage cover.