Abstract: In a box-shaped main body of a nearly rectangular parallelepiped shaped shell, an absorber, an evaporator, a low temperature regenerator, and a condenser are disposed sequentially in the vertical direction from the bottom, and a refrigerant sump of nearly V or U shape is disposed between the evaporator and absorber. Furthermore, an eliminator is disposed in an oblique direction at the side of the evaporator, and a purging enclosing member is disposed in the absorber, and a flush chamber of double structure is installed between the evaporator and refrigerant sump. This slim low temperature shell, and high temperature regenerator and others are formed into one body forming an element or module, and a plurality of elements are disposed parallel in the lateral direction, or disposed in the lateral direction and stacked up in the vertical direction, thereby forming a large-sized absorption chiller/absorption chiller-heater.