2ContentsContents ........................................................................................................ 2Owner's GuideImportant Safety Information ....................................................................... 3General PartsMain Unit .................................................................................................... 8Remote Controller .................................................................................... 9Initial Operation ........................................................................................... 11Setting and Using the Water Heater ........................................................... 12Flow Meter Alarm ......................................................................................... 14Muting the Remote Controller .................................................................... 16Preventing Damage from Freezing ............................................................ 17Regular Maintenance ................................................................................... 19Troubleshooting .......................................................................................... 21Follow-up Service ........................................................................................ 25Specifications .............................................................................................. 26External Outfitting ....................................................................................... 27Combustion Unit and Gas Route ............................................................... 29Hot-Water Feed Route ................................................................................. 31Electronic Control Unit ................................................................................ 33Electronic Control Unit, Remote Controller and Attached Set ................ 34Installation Manual ...................................................................................... 351. Included Accessories ............................................................................ 362. Optional Accessories ............................................................................ 363. Quick Connect Multi System Installation ............................................ 374. Before Installation ................................................................................. 385. Choosing Installation Site .................................................................... 396. Installation Clearances ......................................................................... 407. Installation .............................................................................................. 428. Vent Pipe Installation ............................................................................ 429. Gas Piping .............................................................................................. 4610. Water Piping ........................................................................................... 4811. Plumbing Applications .......................................................................... 4912. Electrical Wiring .................................................................................... 5013. Maintenance ........................................................................................... 5414. Trial Operation ....................................................................................... 5415. Dimensions and Wiring Diagram ......................................................... 55Remote Controller Installation Guide ........................................................ 58