The economizer is installed in the lower part of the flue at the tail of the boiler, and the working principle is to recover the waste heat in the flue gas through heat exchange, thereby improving the overall thermal efficiency of the boiler.

When the flue gas passes through the economizer, the heat is transferred through the metal wall to the water in the pipe, thus heating. This heated water is returned to the boiler, which can greatly improve the combustion efficiency, reduce fuel consumption, and thus achieve the role of energy saving and emission reduction.