an option in many water-tube boilers is the usage of re-circulation pumps.please expalin in which cases/for which purpose is this reasonable?
Natural circulation boilers rely on the density difference of the hot and cold water in the boiler to circulate the boiler water through the tubes. Boilers with recirculating pumps force the water to circulate through the boiler tubes. This creates a more even heating in boiler tubes of different sizes, shapes, and lengths. It allows for faster heating at boiler start-up, larger overall boiler sizes, and more efficient usage of heating surfaces.
