TM 55-1930-209-14&P-19 Table 3-2.  ROWPU System Valves (Continued) Label identification Type Valves Location and Valve Function 3-in. RO19 ROWPU space - in MEMBRANE CLEANING gate valve (Barges board of pretreatment SOLUTION RECIRCULATION; 2 and 3 skid during RO block membrane only) cleaning, allows cleaning solution to recirculate through seawater pump 3-in. R020 ROWPU space - between PRODUCT WATER TO gate valve (Barges RO block and HP pump OVERBOARD; allows flow of 2 and 3 product water from RO block to only) overboard 4-in. RO21 Void 3 port shell PRODUCT WATER gate valve (Barges OVERBOARD DISCHARGE; 2 and 3 allows product water from RO only) block and RO 20 to flow overboard 3-3    ROWPU  System  Description.    The  ROWPU  system  processes  seawater  or  brackish  water  supplied  by  the seawater  system  to  create  drinking  water.    Chlorine  is  added  to  the  processed  water  by  the  chlorination  system.    The resulting drinking water is then discharged into four drinking water storage tanks. Section II Table 3-3.  Preventive Maintenance Checks and Services for ROWPU System B - Before D - Daily Q -  Quarterly D - During W - Weekly S -  Semiannually A - After M - Monthly A -  Annually INTERVAL ITEM PROCEDURES EQUIPMENT ITEM TO BE CHECK FOR AND HAVE IS NOT READY/ NO. INSPECTED REPAIRED OR ADJUSTED AVAILABLE IF B   D   A   D  W  M   Q   S   A AS NECESSARY ROWPU SYSTEM 1 * * * Small Components a.  Wipe components clean, especially pres- Gauges inoperable. sure gauges, flowmeters, indicators and control panels. * * * b.  Check for leaks, paying special attention Pressure drops to joints, valves, fittings and piping. below normal Report uncorrectable leaks to shift leader level. or bargemaster. 3-5