What the tower does
A cooling tower rejects the heat that a water-cooled chiller collects from the building. Warm condenser water sprays over fill material while fans pull air through; a small fraction evaporates, carrying the heat away, and the cooled water returns to the chiller. Evaporation is the whole trick — and it is why the tower consumes water and concentrates whatever is dissolved in it.
Water treatment is not optional
As water evaporates, minerals stay behind and concentrate. Untreated, that means scale on the fill and in the chiller's condenser tubes — an efficiency penalty that compounds into head-pressure trips — plus corrosion and biological growth. A treatment program (chemistry, blowdown control, monitoring) is the cheapest insurance in the plant, and neglected towers are the root cause behind many of the failures in our chiller troubleshooting guide.
Legionella: manage it in writing
Towers are the textbook Legionella habitat — warm water, aerosol drift, organic material. ASHRAE Standard 188 expects buildings to maintain a documented water management plan: monitoring, cleaning schedules, and disinfection procedures. If your building has a tower and no written plan, that is a liability sitting on the roof. Twice-yearly cleaning and disinfection is the working baseline.
Seasonal care
Spring: clean the basin, inspect fill and drift eliminators, service fan drives and belts, verify makeup and blowdown controls. Through summer: chemistry checks and strainer cleaning. Fall: layup or winterization — drained or heat-traced, depending on whether the plant runs winter loads. We fold tower service into plant maintenance programs alongside the chiller and boilers — one contract, one report stream.