Scaling
Water formed deposits resulted from naturally occurring minerals precipitating from water to form scale. The most common scales are calcium carbonate, calcium sulfate and silica or silicates. Scale build up on the surfaces can be extremely hard and difficult to remove. Also, scaling will drastically reduce heat transfer capacity and system energy efficiency.

Corrosion
Cooling systems are exposed to many types of corrosion, from general corrosion to pitting caused by deposits, foulants or microorganisms. Corrosion reduce the life span of equipment by years, incur costly equipment repair, production down time and expensive replacement.

Fouling
Foulants are contributed from make up water, corrosion products or airborne materials, such as mud, sand clay, oils, debris, organics, microbes and etc.these foreign particles adhere to heat transfer surfaces and reduce heat transfer capacity and water flow.

Microbiological Contamination
Microbial problems associated with cooling water system are caused by algae, fungi and bacteria. They can cause plugging, fouling, corrosion and destruction of wooden cooling tower components. Legionella pneumophila, a species of bacteria found in cooling tower may post health hazards to public when improper treatment program applied.