Gage Calibration
GAGE CALIBRATIONBefore evacuating the system, 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 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 the gage as follows:
1. Remove cover from gage.
2. Holding gage pointer adjuster screw firmly in one hand, carefully force pointer in the proper direction to position pointer at "0".
^ Glycerine filled gages will use a rear mounted recalibration screw.
3. Replace gage cover.