3-10. REMOVE/INSTALL MANOMETER - continued.
Using a glass funnel slowly pour the liquid in the fill port until the indicating level is
approximately at the zero at (0) graduation on the scale.
Install the fill plug. Be sure it is tight.
Adjust the scale for the correct zero position in relation to the liquid meniscus.
For consistent results in reading the manometer the same way, always read the
meniscus at eye level. The accuracy of the manometer is verified by using a certified
master gage. Recommended A-level calibration frequency is 180 days.