A cooling tower is a key component in most commercial or industrial HVAC systems. In order to do its job properly, a cooling tower must be kept clean at all times.
By not properly cleaning a cooling tower, you can cause a number of problems including bacteria growth, decreased efficiency, and reduction in the life span of the tower.
Why Cleaning Your Cooling Tower Is So Important
Cooling tower maintenance and cleaning is essential to prevent harmful bacterial buildup and to maximize longevity and efficiency of your equipment. According to the latest OSHA recommendations, you should be cleaning your cooling tower at least twice a year. These are the key reasons you should stay on top of your biannual cooling tower cleanings.
Remove Buildup and Bacteria
The most common reason for cleaning a cooling tower is to remove the buildup of organic growth and biofilms. Cooling towers work like an air scrubber and can bring in different types of debris from the air into the system. When the tower is out of service it can become a breeding ground for bacteria and a buildup of biofilm or slime can lead to legionella growth.
If the system is not professionally cleaned before and after the cooling season, and bacteria is present in the system, legionella can spread into the air. If inhaled this can develop into Legionnaires disease.
Bacteria build up can also reduce the efficiency of heat transferability, clogged piping, and reduced flow. The less efficient your system is, the higher your operating costs. Failing to maintain your system will also reduce the longevity of your equipment as it works harder to produce the same results as if your tower was clean.
Remove Scale and Other Deposits
Another reason for cleaning a cooling tower is to remove scale and other deposits. As we mentioned prior, the cooling tower scrubs different types of debris out of the air and into the system. Cleaning the tower prevents this debris and build up from entering the main components of your HVAC system as well as the tower itself.
Scale build up can create inefficiencies due to restricted air and water flow. If the pumps and fans of the system have to work harder to reach needed water temps, the building’s energy consumption will increase. In addition, the deposits can also cause corrosion and damage to the cooling tower’s components.
Steps to Clean Your Cooling Tower
Thoroughly cleaning your cooling tower is essential for long-term performance and to ensure that no bacterial buildup is able to develop. While every cleaning operation is unique based on the location and type of cooling tower you operate, there are a few key considerations to keep in mind when developing your cooling tower water treatment plan.
Disinfection
Once your system has been shut down, you are ready for chemical disinfection. Most tower cleaning companies use a form of chlorine to chemically disinfect the basin of the tower. This prevents any bacteria that is present from being aerated and spreading through the air during cleaning.
System Shutdown
Before starting your tower cleaning you must first have the tower shut down in order to service it. The building engineer or facilities team can assist with this. If the cleaning is being done during cooling season when the tower is operational, the building may not have air conditioning if the tower being cleaned is the only one on site.
Be sure your building personnel have made tenants aware of this. If you are working on a site with multiple towers, it is important to isolate the tower being worked on by valving off flow via the equalization line. Drain your tower before proceeding.
Hot Deck
After shutdown, you can begin manually cleaning your tower. It’s suggested to clean from the top down so that dirty water and debris is not entering the areas you already cleaned. The top of your tower is called the hot deck. This is where your hot water enters the cooling tower. Open your distribution pans to ensure those are cleaned as well. Use a low pressure hose and if needed a brush to clean the deck and any nozzles.
Tower Surfaces and Basin
Once the hot deck is cleaned you can begin to clean the inside of your tower. The goal is to clean any area that comes in contact with water. This includes your basin, fill, and pans. Remove any sludge, scale, algae, or sediment by using your hose to remove this build up. There should be no debris or biological growth left on the inside of your tower.
Treatment
Once your tower is cleaned and free of all sediment, debris, and organic growth, visually inspect your tower and ensure any parts that may have been removed during cleaning are reinstalled as they were when you arrived. Have the system filled and circulated and add a biocide treatment to further protect against bacteria and legionella.
Reporting
It is best practice to provide reporting or photos of the job to your building engineer or facilities manager. Be sure that report is acceptable to local authorities if working in a jurisdiction that requires these reports. Ensure the tower is operational before leaving the job site.
Keep Your Cooling Tower Running Efficiently All Year Long
Maintaining a cooling tower can be a difficult task, but it is important to keep it clean in order to avoid any unnecessary problems. One way to help maintain your cooling tower is by working with a cooling tower water treatment expert.
These experts can help keep your cooling tower running smoothly and efficiently based on the unique needs of your setup. For more information on how to stay on top of your cooling tower maintenance, reach out to our team of experts today at 212-518-6475.
