The objective of the radiant tube burner is to transfer heat from combustion gases to the radiant tube and then radiate the energy to the load. Radiant tube burners are used in specific heating processes where combustion products cannot come in contact with the load or material. Radiant tube burners are an indirect heating burner meaning the heat is transferred without any direct flame or combustion exhaust. Radiant tube burner systems are designed to reduce nitrous oxide in the burner process. Radiant tube burners include a flue gas recirculating assembly designed to reduce NOx emissions.