The plug-and-play Model 2122 Cooling Tower Control System (CTCS) is designed to apply the various chemicals utilized to prevent corrosion, scaling and fouling. A biocide timer is built into the system for ease of maintenance. It is simple to install, set-up and operate right out of the box. The unit is an integrated system, which controls acid feed, blowdown and inhibitor feed in cooling processes. Acid feed is controlled via pH monitoring, blowdown is controlled via conductivity (TDS) and the inhibitor is fed on a user selected time basis. The optional PHS10 pH sensor and the CS10 conductivity sensor are easily installed and serviceable insertion style devices.