Abstract: There is provided an absorption chiller including: a control unit configured to control opening and closing of the first control valve and an operation of the first pump, and a second supply flow path configured to supply the liquid inside the evaporator into the absorber; a second control valve opening and closing the second supply flow path; and a second pump configured to generate power to supply the liquid inside the evaporator into the absorber. After an operation of the absorption chiller is stopped, the control unit is configured to open the first control valve and operate the first pump such that a liquid inside the evaporator is mixed with the absorption liquid. Further, before the first control valve is opened and the first pump is operated, the control unit is configured to open the second control valve and operate the second pump.