Liquid ventilator and methods integrating the concept of total liquid ventilation (TLV) using liquid volumes below functional residual capacity (FRC) of mammal's lungs are disclosed. Beyond the automatization of the whole process, the technology has been up-scaled to confirm that TLV at residual volumes below FRC can provide a safe procedure while enabling the full potential of TLV in a mammal such as humans or adult-sized animals. Such tidal liquid ventilation strongly differs from the previously known TLV approach, opening promising perspectives for a safer clinical translation. Also disclosed are apparatus and method for safe and fast induction of hypothermia during liquid ventilation of a mammal.