A heat exchanger system for cooling liquid having a plurality of finned tube arrays and a plurality of fans for inducing air through the finned tube array comprising: at least one wind deflector installed along the long side of the finned tube arrays on at least one side of the arrays. The present invention for includes a method for minimizing the undesired effect of wind on the operation of a heat exchanger system for cooling liquid having a plurality of finned tube arrays and a plurality of fans for inducing air through the finned tube array, the method comprising the steps of: setting the angle of deflection of the wind deflectors other than the angle of deflection of the uppermost position of the wind deflectors; collecting readings of outlet temperature sensor of the heat exchanger, ambient temperature, wind sensor and inlet air pressure sensor of the heat exchanger; recording readings of outlet temperature sensor of the heat exchanger, ambient temperature, wind sensor and inlet air pressure sensor of the heat exchanger; comparing readings of outlet temperature sensor of the heat exchanger, ambient temperature, wind sensor and inlet air pressure sensor of the heat exchanger to previous readings; and carrying out a correction command if the readings have changed.