1. Specifications/Performance TableSpecificationsSpecificationNR501-ODOutdoor Wall MountedDirect Ignition15-150 psi0.5 GPM (2 L/min.)32 lbs.0.15 Gallon (0.5L)3/4"3/4”1/2”120 VAC (60Hz)Zincified Steel Plate/Polyester CoatingStainless SteelCopper Sheeting, Copper TubingStainless Steel Sheeting, Stainless Steel TubingFlame Rod, Thermal Fuse, Lightning ProtectionDevice (ZNR), Overheat Prevention Device, FreezingPrevention Device, Fan Rotation DetectorRemote Controller, Remote Controller Cord,Cross Recessed head screwItemModel NameTypeIgnitionOperating PressureMinimum Flow RateDimensions (Height) x (Width) x (Depth)WeightWater Holding CapacityAccessoriesInstallationAir Supply/ExhaustConnection SizesPower SupplyMaterialsWater InletHot Water OutletGas InletCondensate DrainSafety DevicesCasingFlue CollarPrimary Heat ExchangerSecondary Heat ExchangerSupplyConsumptionPower VentedNG : 35W LP : 38WFreeze Prevention 139W20.5" (520mm) x 13.8"(350mm) x 6.7" (170mm)N/AN/ANR501-ODNR662-OD3SpecificationNR662-ODOutdoor Wall MountedDirect Ignition15-150 psi0.5 GPM (2 L/min.)35 lbs.0.15 Gallon (0.5L)3/4"3/4”3/4”120 VAC (60Hz)Zincified Steel Plate/Polyester CoatingStainless SteelCopper Sheeting, Copper TubingStainless Steel Sheeting, Stainless Steel TubingFlame Rod, Thermal Fuse, Lightning ProtectionDevice (ZNR), Overheat Prevention Device, FreezingPrevention Device, Fan Rotation DetectorRemote Controller, Remote Controller Cord,Cross Recessed head screwItemModel NameTypeIgnitionOperating PressureMinimum Flow RateDimensions (Height) x (Width) x (Depth)WeightWater Holding CapacityAccessoriesInstallationAir Supply/ExhaustConnection SizesPower SupplyMaterialsWater InletHot Water OutletGas InletCondensate DrainSafety DevicesCasingFlue CollarPrimary Heat ExchangerSecondary Heat ExchangerSupplyConsumptionPower VentedNG : 38W LP : 39WFreeze Prevention 139W20.5" (520mm) x 13.8"(350mm) x 6.7" (170mm)