← Cooling Towers

Cooling Tower

A cooling tower rejects heat from condenser or process water to the atmosphere by evaporation: warm water spreads over fill media while a fan draws air through it, cooling the water for return to chillers or process loops. The catalog lists 78 models from brands including Marley, Evapco, Baltimore Aircoil Company, Thermal Care, Delta Cooling Towers, Tower Tech, and Recold.

Modèles

Sized by ton

Nominal capacity

Marques

Fonctionnement

Warm water from the condenser loop distributes over fill — thin sheets or splash surfaces that maximize air-water contact. A fan moves air through the fill, evaporating a small fraction of the water and carrying the heat away; the cooled water collects in a basin and pumps back to the load. Drift eliminators capture entrained droplets, and makeup water replaces evaporation and blowdown. Closed-circuit variants keep process fluid inside a coil, spraying water over the coil so the loop stays clean while heat still leaves by evaporation.

Types et variantes

Open-circuit induced-draft towers: The standard configuration — a top fan pulls air through fill in direct water contact.
Forced-draft towers: Fans push air into the tower; common in compact and indoor-ducted designs.
Closed-circuit fluid coolers: Coil-isolated loops for clean process fluid with evaporative performance.
Portable and temporary towers: Skid- or trailer-mounted towers for outages, shutdowns, and project loads.
Crossflow and counterflow designs: Air path geometries trading height, footprint, and maintenance access.

Spécifications clés

Spécification	Plage typique	Signification
Nominal capacity	Sized by ton	Heat rejection rating matched to the chiller or process load.
Design water flow	Varies by model and capacity	The gpm the tower is rated to cool through its design temperature range.
Fan power	Varies by model and capacity	Drives airflow and thus thermal performance and sound level.
Approach temperature	Varies by selection and site conditions	How close the leaving water gets to ambient wet-bulb — the core performance measure.

Comment l'industrie le dimensionne

Cooling towers are sized by heat rejection in nominal tons at design wet-bulb, flow, and range. Selection matches the chiller or process load at the site's design wet-bulb temperature, then checks footprint, water treatment, and electrical supply. Units from 0 to 200 tons reject heat from a single water-cooled chiller or one process loop; 200 to 500 ton units serve as standard temporary towers for a building's chilled water plant during an outage; 500 to 1,000 ton towers handle large plant and process cooling — usually two or more chillers on one tower; units above 1,000 tons provide plant-scale heat rejection for refinery, power, and data-centre turnarounds.

Applications

Condenser water cooling for chiller plants
Process cooling for manufacturing and industrial loads
Temporary heat rejection during shutdowns and tower replacements
Data center and campus central plant support
Supplemental capacity for peak-season loads

Sécurité et opération

Cooling towers can harbor Legionella; ASHRAE 188 water management programs — treatment, monitoring, cleaning — are the controlling practice.
Fan and pump lockout precedes any basin, fill, or mechanical work.
Tower access involves work at height; ladders, platforms, and fall protection follow OSHA requirements.
Chemical water treatment is handled per its hazard documentation, away from drift and intake paths.

Normes et certifications

CTI · STD-201: Thermal performance certification for evaporative heat rejection equipment.
ASHRAE · 188: Legionellosis risk management for building water systems, including cooling towers.
NFPA · 214: Fire protection standard for water-cooling towers.

Questions fréquentes

How much water does a tower consume?

Evaporation carries away roughly the heat load's equivalent in water, plus blowdown to control dissolved solids. Makeup water supply and treatment are part of every installation plan.

Open or closed circuit — how is the choice made?

Open towers are simpler and cheaper per ton; closed-circuit fluid coolers keep the process loop sealed and clean at some performance and cost premium — decisive where loop fouling is unacceptable.

What is approach and why does it matter?

The gap between leaving water temperature and ambient wet-bulb. Tight approaches need more fill and fan — a tower cannot cool below wet-bulb, so local climate bounds the achievable water temperature.