Fig. 5: Minimum Clearances from CombustibleSurfaces – Indoor and Outdoor InstallationsRoof water drainage must be diverted away fromheaters installed under overhangs.HeaterSideMin. Clearancefrom CombustibleSurfacesMinimumServiceClearanceRear 12” 36”Right Side 1” 24”Left Side 1” 1”Top Unobstructed 10”VentTermination12” 12”Table D: Clearances – Outdoor InstallationsService clearances less than the minimum mayrequire removal of the heater to service either the heatexchanger or the burner components. In either case,the heater must be installed in a manner that willenable the heater to be serviced without removing anystructure around the heater.Outdoor InstallationsThese heaters are design-certified for outdoor installa-tion. Heaters must not be installed under an overhangunless they are in accordance with local installationcodes and the requirements of the gas supplier. Threesides must be open in the area under the overhang.Combustion and Ventilation AirIndoor UnitsThis heater must be supplied with sufficient quantitiesof non-contaminated air to support proper combustionand equipment ventilation. Combustion air can be sup-plied via conventional means where combustion air isdrawn from the area immediately surrounding theheater, or via direct vent, where combustion air isdrawn directly from outside. All installations must com-ply with the requirements of the NFGC (U.S.) andB149 (Canada), and all local codes.NOTE: Use of this heater in construction areaswhere fine particulate matter, such as concrete ordry-wall dust, is present may result in damage to theheater that is not covered by the warranty. Ifoperated in a construction environment, a cleansource of combustion air must be provided directly tothe heater.CAUTION: Combustion air must not becontaminated by corrosive chemical fumes whichcan damage the heater and void the warranty. (Seethe Appendix.)NOTE: It is recommended that the intake vent beinsulated to minimize sweating.Venting not shown for clarity. Heater must be vented per instruc-tions in this manualCalifornia Hot Water Supply, Inc.(800) 249-72449