Ammonia recirculation can be used in a variety of industrial refrigeration applications. Liquid ammonia refrigerant is fed into the pump accumulator to maintain a controlled liquid level. The liquid is then mechanically pumped to the evaporators at approximately 25 psi greater than the suction pressure and at a rate greater than the evaporation rate. After leaving the evaporators, the liquid and vapor return to the suction accumulator where separation takes place. The liquid is then recirculated to the evaporator with make-up liquid supply, and the dry suction gas goes to the compressor.