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Cooling Towers

Cooling towers are heat removal devices used to transfer process waste heat to the atmosphere.

Cooling towers are heat removal devices used to transfer process waste heat to the atmosphere, and they may either use the evaporation of water to remove process heat and cool the working fluid to near the wet-bulb air temperature or, in the case of closed circuit dry cooling towers, rely solely on air to cool the working fluid to near the dry-bulb air temperature.

Common applications include cooling the circulating water used in oil refineries, petrochemical and other chemical plants, thermal power stations and HVAC systems for cooling buildings.

The main types of cooling towers are natural draft and induced draft cooling towers (The classification is based on the type of air induction into the tower).

HVAC (heating, ventilation, and air conditioning)

HVAC (heating, ventilation, and air conditioning) is important in the design of medium to large industrial and office buildings such as skyscrapers and in marine environments such as aquariums, where safe and healthy building conditions are regulated with respect to temperature and humidity, using fresh air from outdoors.

Why is it important to regularly service cooling towers?
There’s always slime build up in cooling towers resulting in insufficient heat transfer. Heat transfer takes place where a cold surface cools the water down. Slime insulates the surface and the heat transfer doesn’t take place and therefore this surface needs to be cleaned.
A factor that may interrupt heat exchange
Another factor that may interrupt heat exchange is the build up of scale due to water hardness. ManChem produces highly efficient anti-scale agents to prevent this kind of build up in cooling towers. Our regular servicing covers cooling water treatment for open, once through and closed systems.
Water treatment programs
Most water treatment programs include water softeners, inhibitors and other chemicals needed to ‘treat’ the water in order to reach the desired conditions for heat transfer. Products used to maintain proper water conditions are often fed automatically by sophisticated equipment directly into a chiller or boiler’s water. Water is used for both cooling and heating in large commercial building applications. In most industrial environments water is used for cooling production equipment or an ingredient to making a product. How the water is used will determine what type of treatment is necessary.

Most water treatment companies use test kits and chemical dispensing systems which have made the use of water treatment chemicals in chiller, boiler and cooling-tower systems much easier. But attention to details, such as how often systems are tested, is critical to system performance. The correct water treatment chemistry at the correct time is extraordinarily important because even minor problems can create major costs.

The Manchem difference
ManChem has its own in-house laboratory – its team comprises of a formulation chemist, biochemist, forensic chemist and microbiologist. Together with manufacturing its own products backed up with direct technical support, Manchem is able to offer cost effective products and services by eliminating the ‘middle man’ service providers.

ManChem also supplies equipment needed for the biocides, inhibitors and antiscalants used in the cooling towers.

How does poor or no service affect cooling towers, chillers or boilers?
Improper water treatment or no treatment at all will increase your energy consumption and operating cost while decreasing your cooling tower’s efficiency and life expectancy. A well designed and implemented water treatment program is highly important to the operation of any steam boiler, centrifugal chiller or cooling tower. All three of the systems utilize water for cooling and heating.

Poor water treatment lets water interact with the surfaces of pipes and vessels which contain it. Steam boilers can scale up or corrode and these deposits will mean more fuel is needed to heat the same amount of water. Cooling towers can scale up and corrode, but left untreated, the warm, dirty water they can contain, will encourage bacteria to grow, and Legionnaires’ Disease can be the fatal consequence. The condenser tubes within a chiller and other water cooling equipment can also scale up and corrode thus preventing good heat transfer. Increased energy consumption and poor cooling performance is the common result in inefficient water treatment.

Water treatment can often be categorized as ‘low-tech’ and unglamorous. However, the right chemicals, proper chemical feed equipment, and a dedicated service provider is essential to your mechanical equipment and should be ‘treated’ with top priority.


  • Monitoring of the various systems, to ascertain that the respective chemistries adhere to the set parameters.
  • Equipment inspection, to ensure correct functioning and operation.
  • Bi-annual Legionella sampling of the cooling tower and make-up (optional as selected by customer).
  • Manchem will keep, provide and maintain an adequate stock of all the chemicals required to perform the Services.