(2) Tolerance of readings shall be:
300 psi (21 .09 kg/cm2)
297303 psi (20.8721.3 kg/cm2)
600 psi (42. 18 kg/cm2)
588612 psi (41.3443.02 kg/cm2)
900 psi (63.27 kg/cm2)
88291 8 psi (62.064.54 kg/cm2)
1200 psi (84.36 kg/cm2)
11881212 psi (83.5185.20 kg/cm2)
1500 psi (1 05.45 kg/cm2)
14851515 psi (104.4106.50 kg/cm2)
(3) Test shall be accurate between 0° to 150°F (18° to 65.5 C).
(4) If gage does not meet accuracy test, replace gage.
f. Repair or Replace.
(1) Reseal crystal into case, if loose.
(2) Conduct a corrosion control program when coating shows signs of pitting in the form of deep cavities
of small diameter (either localized or over large areas), peeling of the case coatings, cracks, abrasions, or
chemical deterioration where dissimilar metals meet (particularly where gage metal meets mounting hardware or
(3) Tighten loose connections to pressure system.
(4) Replace damaged, unrepairable, or unserviceable gage assembly.
3-23. R.O. VESSELS GAGE.
a. General. Gages must be tested periodically for accuracy. The R.O. VESSELS gage shows the pounds per
square inch pressure drop between the input and the output of the R.O. vessels. The gage helps to determine
when R.O. elements need changing. This paragraph covers cleaning, inspection, and testing of the R.O.
b. Removal. If necessary, remove R.O. vessels gage assembly in accordance with paragraph 268.
(1) Clean threads of the coupling nuts.
(2) Clean gage crystal on outside with a mixture of water, a few drops of vinegar, and a few drops of liquid
(3) Flush the inside of the gage by filling, soaking, draining, and drying the bourdon tube.