Gases: Natural or PropaneCapacity: 1, 500, 000 Btuh maximum 850, 000 Btuh minimumOrifice Size: 41 DMS (X46)Blower: 7, 000 cfmElectrical Rating: 115 volts, 60 Hz, 9.4 amps, Single PhaseMin. Temperature Rating: Minus 40 degrees FGas Supply:Inlet Pressure Manifold PressureMax W.C. Min W.C. Max W.C. Min.W.C.Propane 14" 9" 2.7" 0.75"Natural 14" 9" 7.2" 2.0"(Minimum inlet pressure is for purpose of input adjustment) Page 6 S1505B Manual 974-9308 Rev. 4.21; Aug 8 2008InstallationThe Sure Flame Model S1505B is a direct fired gas heater