Adjustable louver system for radiant heat transfer control in a
Apparatus for radiant heat transfer
Boiler
Boiler
Boiler assembly
Boiler element
Boiler heat exchanger unit
Boiler structure embodying a plurality of heat exchange units
Boiler with increased flame temperature and output
Catalytic combustion heat exchanger
Catalytic combustion heater
Catalytic combustion heater
Catalytic combustion heater
Coal-fired heating apparatus and method
Coil tube heater for a used-oil fired furnace
Combustion device in tube nested boiler and its method of combus
Combustion device in tube nested boiler and its method of combus
Combustion method and apparatus for NOx reduction
Compact boiler having low NO.sub.x emissions
Compact boiler having low NOX emissions