CBL0647-M13 COPPER-FIN HOT WATER BOILER 645MBH INPUT PROPANE GAS >81% THERMAL EFFICIENCY >8" VENT CONNECTION >CSD-1 FIRING CONTROLS >ADJ HIGH LIMIT W/MANUAL RESET >ASME COPPER-FIN HEAT EXCHGR. >COMBUSTION AIR FILTER >FLOW SWITCH >LOW WATER CUTOFF W/MANUAL RESET LOCHINVAR