820 STEAM AND HOT WATER BOILERS, STEAM HEATING, AND POWER PLANT EQUIPMENT 82004 * After-Coolers and Condensers 82006 * A.S.M.E. Code Tanks 82008 * Boilers, High Pressure 82012 * Boilers, Low Pressure 82016 * Boiler Tubes 82020 * Blow-Off Basins 82024 * Blow-Off Valves 82028 * Burners, Gas and Oil 82032 * Chemical Feed Systems (For Proportioning Pumps See Class 720) 82036 * Coils, Steam Heating 82038 * Condensate Return Systems: Vacuum Heat Pumps, Wet Vacuum Pumps, etc. 82040 * Controls: Combustion, Fuel Cut-Off, Hardness, High-Low Water Level, Ignition, etc. 82044 * Convectors and Radiators 82048 * Deaerating Units 82052 * Draft Fans and Draft Gauges 82056 * Feedwater Heaters 82060 * Feedwater Injectors 82064 * Filters, Boiler Water 82068 * Heat Exchangers, Accessories, and Parts 82072 * Hot Water Generators 82076 * Oil Purifiers 82084 * Stacks, Steel 82086 * Steam Flow Transmitters 82088 * Tube Cleaners and Tube Expanders 82092 * Turbines, Steam Driven 82093 * Turbines, Water (Hydraulic) Including Accessories and Parts 82095 * Valves, Spherical