As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLT DIVERTED DUE TO NO WATER PRESSURE IN ENTIRE ACFT. PERFORMED OPS CHECK OF WATER SYS ALSO OPS CHECK PRESELECT WATER VALVE ABOVE CEILING PANEL IN FIRST CLASS, ALSO CHK DRAIN VALVE, PRESURE CHECK WITH AND WITHOUT APU BLEED, ALSO REFILLED WATER TO FULL. UNABLE TO DUPLICATE PROBLEM. SYS CHECKS OK.