+1 to this. The cooling tower ought to be in the secondary circuit - a refrigerant is used in the primary circuit to cool the air in the evaporator - the inside unit of the air conditioner, and condensed back to a liquid in the condenser, with the heat being removed by the secondary circuit water. The water gets warmed up and then cooled down again in the cooling tower.

Was the party out on the terrace near the cooling towers where the legionnaires were exposed to the cooling tower spray carried by the wind?