device for vermealstrare including vermevexlingsytor separates a uppvermningsgas from another medium to uppvermas

摘要

An apparatus for heating a first fluid such as water or the like by moving such fluid in counterflow heat exchange relationship with a heated second fluid such as air. A spiral wall is provided in a portion of the apparatus which defines a spiral passageway for the heated fluid and such wall includes at least one conduit for the fluid to be heated. A removable wall normally closes one end of the heated area and the spiral wall to provide access thereto when the wall is removed.