A refrigerant subcooling system including a water collector configured to collect water condensate from an evaporator. A heat exchanger defines a channel configured to accommodate a refrigerant conduit extending therethrough. The heat exchanger includes a water mist generator connected to the water collector by a water line to receive the water condensate from the water collector. The water mist generator is configured to generate a mist of the water condensate that mixes with air flowing through the channel and along the refrigerant conduit to cool refrigerant therein.