Agitator finds its applications at places where different temperatures/densities of liquid exist in the same system e.g. Hot and cold liquid, Agitators can be used at places where the above mentioned conditions exist in a system to make these variables uniform in the entire system, like in ice banks where ice is produced on evaporating coils. Without agitators, there would be no circulation of water in the tanks, it would have different densities and temperatures at different locations in the tank.