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■What changes with cooling tower cleaning? The purpose of cleaning a cooling tower is to remove dirt, but it ultimately contributes to maintaining the cooling tower's capacity. When scale and slime accumulate, the heat exchange efficiency decreases, and the load on fans and pumps increases. Therefore, if cleaning improves the performance of the equipment, it can reduce power consumption and lead to lower electricity costs. ■Why are legal measures necessary? If air conditioning equipment is installed, measures must be taken to prevent indoor air from being contaminated by pathogens. This is to address the "Legionella" bacteria that can cause Legionnaires' disease. According to the Building Sanitation Law, regular inspections and cleaning of cooling towers and cooling water are required for applicable buildings. ■How often should cleaning be done? Generally, cleaning and water replacement should be done at least once a year. If dirt in the cooling tower is left unattended, it can lead to inadequate hygiene management, making regular cleaning essential not only for maintaining capacity but also for infection control. Please feel free to consult us first.

■Why do Legionella bacteria increase in cooling towers? The water temperature in air conditioning cooling water systems generally ranges from 10°C to 40°C. The optimal temperature for the growth of Legionella bacteria is around 36°C (the temperature range for proliferation is 25°C to 43°C), and from May to September, the water temperature in cooling systems approaches the optimal temperature for the proliferation of Legionella bacteria. ■How do Legionella bacteria proliferate? Legionella bacteria are known to proliferate by parasitizing amoebas. Environments where slime develops on the cooling tower itself or on the walls of pipes are believed to promote the growth of Legionella bacteria. ■What is Legionnaires' disease? The main forms of Legionnaires' disease are severe Legionella pneumonia and mild Pontiac fever. Legionella pneumonia begins with symptoms such as general fatigue, headache, loss of appetite, and muscle pain, and can progress to coughing, high fever above 38°C, chills, chest pain, and difficulty breathing. Rarely, symptoms outside the lungs, such as myocarditis, may also occur. ■How can risks be prevented? Regular water quality management, such as controlling the water temperature and preventing slime formation, is key to preventing the proliferation of Legionella bacteria. Please feel free to consult us for more information.

■What inspection obligations are there for cooling towers? Inspections of cooling towers are required to be conducted once at the start of use and once within one month after starting use, regularly checking the condition of dirt and performing cleaning or water replacement as necessary. However, periods of non-use exceeding one month are excluded from this requirement. Additionally, cleaning of the cooling tower, water pipes, and humidifying devices must be done regularly once within a year. ■What should be checked during inspections? The operational condition of the drive mechanism, adjustment of the V-belt, gear oil level of the reduction gear, and the presence of vibrations or abnormal sounds should be checked. For the upper water tank, in square cooling towers, the clogging of the spray holes should be inspected, and in round cooling towers, the adjustment of rotation should be checked. ■How is water quality checked? In addition to checking for carryover, the water quality of circulating water and make-up water is tested by measuring conductivity. ■What happens if inspections are neglected? Neglecting inspections can lead to various risks being overlooked, such as the accumulation of scale and slime, and the proliferation of Legionella bacteria. Please feel free to consult us first.

■Why are cooling towers prone to freezing? Water freezes when it drops below 0 degrees Celsius (freezing point). Cooling towers are designed to spray water into the air and cool it through evaporation, making circulating water, spray water, and makeup water easily exposed to outside air and wind. This creates a risk of freezing, especially during winter. It is generally said that it is too late to address freezing issues once they occur. ■Why do devices break when freezing occurs? When water freezes and turns into ice, it is said to expand in volume by about 9 percent. If this expansion occurs within pipes, it can cause a rapid increase in internal pressure, leading to damage to the pipes and fittings. The reason freezing damage is considered "too late once it happens" lies in this physical phenomenon of volume expansion. ■What happens if freezing is left unattended? If the circulating water, spray water, and makeup water in the cooling tower freeze, it can render the cooling tower inoperable, prolong recovery time, and result in significant costs. What actions to take to prevent freezing becomes a crucial key point. ■What preparations can be made regularly? In addition to managing the water quality of the cooling water system, during periods when freezing is a concern, it is important to maintain operations without stopping the circulating water and to insulate the pipes. Regular preparations are key to preventing damage. Please feel free to consult with us first.

■What is scale? Cooling towers can develop scale over long periods of use. Scale is the accumulation of "minerals" such as calcium and magnesium. Specifically, it includes calcium, magnesium, silica, and iron. ■Why does scale form? Cooling towers operate by evaporating a portion of the water, using the heat of vaporization to cool the remaining water. Only water molecules evaporate, leaving the minerals behind, which increases the concentration of minerals in the water as the cycle repeats. This "evaporation concentration" causes the minerals to become insoluble, resulting in the crystallization that forms scale. ■Where and what kind of damage occurs? Scale can attach not only inside the cooling tower but also to heat exchangers, copper pipes, and plumbing. If not detected early, the damage could become significant. Scale issues can severely reduce the cooling tower's efficiency and corrode metals. ■What are the key points for countermeasures? As long as cooling towers are in use, scale removal is essential. Regular water quality management and periodic inspections and cleaning are crucial to prevent efficiency loss and corrosion. Please feel free to consult us first.

■Why are measures different depending on the location? The freezing prevention measures for cooling towers change depending on whether the water is moving or stagnant. Generally, water is less likely to freeze as long as it continues to circulate, while stagnant water has a higher risk of freezing. The measures can be divided into three patterns: continue circulating, drain the water, or insulate. ■What are the specific measures for each location? Insulation material is wrapped around the piping on the supply water side. For closed cooling towers, either keep the circulation pump running or drain the closed side cooling water. The backup circulation pump, which is currently stopped, should either have the water drained or be wrapped in insulation material. Insulation material is also wrapped around cast iron valves and glass flow meters. For faucets where the water flow has stopped, either leave it slightly open or wrap it in insulation material. ■What is the common approach? The commonality among the six locations is the idea of either "keeping it moving," "draining," or "insulating," which prevents the conditions for water to freeze (stagnation and low temperature). Equipment that is stopped is often overlooked, so caution is necessary. ■Summary The state of water around cooling towers varies by location, and uniform measures are insufficient. Taking measures while checking the condition of each piece of equipment is key to preventing freezing damage. Please feel free to consult us first.

■What is a cooling tower? A cooling tower is a device that cools cooling water. It serves the purpose of releasing heat from indoors to the outdoors and is installed on the rooftops of large facilities such as buildings and shopping malls. Hot water is sprayed from the top, and air is blown from the bottom to facilitate contact with the water, causing it to evaporate. It is used for heat rejection in air conditioning chillers of buildings and for cooling water treatment in factory production equipment. ■Why does evaporation cool the water? When water evaporates, it absorbs heat (latent heat of evaporation) from the surroundings, which cools the remaining water. This is the same principle as how the body feels cooler when sweat evaporates. ■How is it different from a chiller? While a chiller also operates on a similar cooling principle, the difference is that a cooling tower allows water to come into direct contact with air under atmospheric pressure for evaporation. ■What types of cooling towers are there? Cooling towers can be broadly classified into "open" types, which directly contact water with outside air, and "closed" types, where water does not come into contact with outside air. Open types are relatively inexpensive, while closed types have the advantage of being less prone to water contamination and concentration. Please feel free to consult us first.

■What is the difference in purpose between a cooling tower and a chiller? The purpose of a cooling tower is to cool down the cooling water that has risen in temperature due to air conditioning systems, using the power of outside air. On the other hand, while a chiller is also used to cool liquids within machinery, its purpose is not just to "cool" but also to maintain a constant temperature of the target (temperature control). ■What does a chiller do? A chiller is a general term for a device that circulates low-temperature heat transfer media, such as water, to cool or heat a target sample or equipment, thereby controlling the temperature. It is often used for cooling, which is why it is called a chiller, derived from the English word "chill," meaning "to cool." It is widely used in equipment that performs precise processing, such as laser processing machines, injection molding machines, and machine tools. ■Why is it necessary to maintain a constant temperature? If the temperature fluctuates during processing, the material may expand or contract due to heat, leading to changes in dimensions and affecting processing accuracy. Keeping the temperature constant with a chiller is important to prevent such impacts on precision. ■Which one should you choose? If you only want to lower the temperature of the cooling water, a cooling tower is sufficient. If you want to maintain the target temperature precisely and consistently, a chiller is more suitable. Please feel free to consult us first.

■What happens if cooling water is left untreated? If cooling water circulating in a cooling tower is operated without treatment, it may lead to the occurrence of what are called the "three major issues" in the cooling water system: corrosion, slime, and scale. Corrosion issues arise from the corrosion of metals, scale issues are caused by the deposition of minerals, and slime issues occur due to the attachment of algae and bacteria, which can lead to a decline in equipment performance and the risk of sudden operational shutdowns. ■What is the problem with Legionella bacteria? If cooling water is left unattended, it can lead to the growth of "Legionella bacteria," which causes Legionnaires' disease. Cooling towers are considered to be conducive to the proliferation of Legionella bacteria due to water temperature and quality conditions, and the Ministry of Health, Labour and Welfare continuously calls for proper management of cooling towers. ■Why are water treatment agents necessary? To prevent these issues and health risks, it is necessary to not only perform rust prevention, scale prevention, and slime control but also to manage water quality with an awareness of Legionella bacteria. For this purpose, water treatment agents are used. Please feel free to consult with us.

Cooling water contains sufficient nutrients at an optimal temperature for the proliferation of microorganisms. As a result, bacteria, germs, and algae thrive in many cooling water systems, moving and adhering throughout the system along with the water. The accumulation of microorganisms or substances secreted by them is referred to as slime. ■What problems can occur? 1. Decreased cooling capacity If slime accumulates on the fill media of cooling towers, piping, or tubes of chillers, the efficiency of the cooling tower will decrease. A reduction in the efficiency of the cooling water leads to a decline in the overall performance of the heat source system. 2. Corrosion of pipes Not only does the water quality of the cooling water passing through pipes with slime adhere deteriorate, but the pipes themselves also suffer damage. This increases the risk of corrosion leading to water leaks, as well as the hassle and costs associated with repairs or replacements. 3. Clogging of pipes Slime is adhesive, and as it accumulates in large quantities, it can hinder the flow of cooling water, leading to the risk of clogs that render the system unusable.

Our company is working to extend the lifespan of cooling towers and reduce costs through energy-efficient operations. We support water treatment plans to prevent pipe corrosion, efficiency diagnostics for cooling towers, inspections and cleaning within the cooling towers, and the removal of harmful bacteria. By implementing proper management and inspections, we can prevent various troubles before they occur. 【For concerns like these】 ■ Noticeable dirt on the cooling tower ■ Increased power consumption ■ Water temperature not decreasing ■ Unusual noises, etc. *For more details, please download the PDF or feel free to contact us.