Whether you maintain one of the skyscrapers overlooking Manhattan’s skyline or an industrial plant in Pittsburgh, all of them have one thing in common: cooling towers. Using the principle of heat transfer, these systems maintain the desired temperature in your facility.
But without regular cleaning, cooling towers can’t run efficiently and safely. Regular cleaning keeps problems like scaling, biofilm, and leaks at bay, which can affect your system’s performance and compromise safety.
Let’s learn more about cooling tower cleaning and maintenance, starting with what it is and why it matters so much.
Why Cooling Tower Cleaning Matters
Your cooling tower runs around the clock to support the comfort of your tenants or to run your industrial process smoothly. But without proper cooling tower cleaning, your system risks scale buildup, corrosion, and harmful microbial growth.
These problems lower efficiency, raise energy costs, and may even lead to public health issues like Legionnaires’ disease. Routine cleaning not only keeps your tower running smoothly but also extends its lifespan and reduces emergency repair costs.
What Does Cleaning a Cooling Tower Involve
Cleaning a cooling tower is not just about removing dirt. This process clears scale, biofilm, and debris from your system’s core components, such as the basins, fill media, drift eliminators, and nozzles.
Professionals typically use both mechanical methods and chemicals for cleaning cooling towers.
For one, it reduces the risk of health risks like Legionella outbreaks. Secondly, scale inhibitors, pH-balancing chemicals, and other cleaning agents help boost the overall performance.
Preparing for Cooling Tower Cleaning
Cleaning a cooling tower is an intricate process. As your tower will be shut during the cleanup, you’ve to plan the whole process from start to finish, so your building or plant remains closed for the shortest possible duration.
So, before you switch off your tower, make sure to:
- Review Your Maintenance Checklist
Every building or plant has a cooling tower maintenance checklist; start with yours. This document outlines past cleanings, inspections, and any repairs your system underwent. Reviewing it helps you plan what needs extra attention this time, whether it’s the fill media, basin, or drift eliminators. - Focus on Safety
Safety must always come first. Cleaning a cooling tower means you’ll work in confined spaces, with heavy equipment, and hazardous chemicals. Your cleaning crew must wear PPE like gloves, goggles, respirators, and protective clothing.
Additionally, train your team to follow Lockout or Tagout (LOTO) procedures to prevent accidental startups during cleaning. Following these safety steps protects both your crew and your equipment.
Step-by-Step Cooling Tower Cleaning Process
Now that you know why regular cooling tower cleaning matters and how to prepare for the process, let’s learn what actually goes into it.
Step 1: Shut Down and Drain the Cooling Tower
Shut it down before you start cleaning a cooling tower. Turn off the power to the cooling tower, including the fans and water pumps. It keeps your cleaning crew safe and also reduces the risk of contaminating other parts of the system.
Next, drain the cooling tower completely to remove any residual contaminants. This includes water from the basin, distribution system, and any remaining in the pipes. Draining the water helps you clean the internal components more efficiently.
Step 2: Clean Tower Components Mechanically
Once the system is drained and shut down, focus on the basin and fill media. Remove any large debris, dirt, and sludge that may have accumulated in the basin. You can use scrapers to clear out the sediment.
Afterward, scale and mineral deposits should be removed using pressure washing or a mild acid solution, depending on the severity of the buildup. This prevents clogs and keeps the water flowing freely through the system. Likewise, clean the fill media, which plays a key role in heat exchange.
The next items on your cooling tower maintenance checklist are fans, pumps, and nozzles. These parts maintain proper air and water flow throughout the cooling tower.
- Fans:
- Check for signs of wear, corrosion, or damage.
- Clean the blades to remove dust or biological buildup that could affect airflow.
- Pumps:
- Inspect for leaks, corrosion, and smooth operation.
- Lubricate moving parts as necessary to maintain efficiency.
- Nozzles:
- Clear any blockages to ensure proper water distribution.
- Prevent uneven water distribution, which can lead to hot spots or inefficient cooling.
Step 3: Use Cooling Tower Cleaning Chemicals
After mechanical cleaning, use chemicals to clean and maintain different parts of your system. Typically, you can use these three cooling tower cleaning chemicals:
- Biocides for Microbial Control
Biocides help eliminate bacteria, algae, and fungi that can build up in the cooling tower. They prevent biofilm formation, which can cause blockages, reduce heat exchange efficiency, and increase the risk of Legionella outbreaks.
Some common biocides are:- Chlorine is a powerful disinfectant widely used to kill bacteria and algae.
- Bromine is typically used in water with a higher pH since it provides a longer-lasting effect.
- Glutaraldehyde is a non-oxidizing biocide that targets specific microbes, and it’s commonly used in high-contaminant environments.
- Isothiazolinones are effective in controlling algae and fungi, and are usually used in cooling tower water treatment.
- Scale and Corrosion Inhibitors
Scale inhibitors, like phosphonates, prevent the accumulation of calcium, magnesium, and other minerals that can form hard deposits inside the cooling tower. They form a protective layer on metal surfaces, reducing rust and deterioration caused by water and oxygen exposure. These cooling tower cleaning chemicals help maintain the efficiency of your system and reduce the need for costly repairs. - Choose Safe Yet Effective Chemicals
While cleaning a cooling tower is important, you must always choose chemicals that are safe for both the environment and your crew. These chemicals should also be compatible with your cooling tower’s materials and the type of water used.
Given what’s at stake, it’s best to work with a professional cooling tower cleaning service. They help you decide and choose the right balance of chemicals, as overuse or incorrect application can damage your system and the environment.
Step 4: Flush and Refill the System
After the cleaning chemicals have had their effect, rinse the system thoroughly to remove any residue. Flushing completely washes out any remaining biocides, scale inhibitors, or other cleaning agents.
Once the system is completely flushed, refill the cooling tower with fresh water. This water must be properly treated to meet the required pH, hardness, and chemical balance, which helps prevent future scale buildup and microbial growth.
Step 5: Final Inspection and Restart
Before restarting the cooling tower, review your cooling tower maintenance checklist to confirm that all components have been properly cleaned and are in good working order. Check the basin, fill media, fans, pumps, nozzles, and all mechanical parts for any issues. Make sure your system is free of any debris, scale, or buildup and that all moving parts are functioning smoothly.
You can restart the system after the inspection. Gradually bring the fans, pumps, and water distribution system back online to avoid any sudden strain on the equipment. After restarting, closely monitor the system’s performance for any irregularities, such as unusual sounds, leaks, or fluctuations in water flow. Continuous monitoring for the first few hours.
Bonus Tip: Establish a Regular Cleaning Schedule
Cooling tower cleaning is most effective when done on a schedule. Most towers need a full cleaning at least once every quarter. Seasonal adjustments will also help your system run without unplanned downtime.
- Run a thorough check and make adjustments before summer to prepare for heavy loads.
- Do the same before winter to prevent damage from freezing.
Combine preventive maintenance with cleaning for the best results, as this keeps your system safe and efficient year-round.
FAQs About Cooling Tower Cleaning
- How often should cooling towers be cleaned?
Most systems need cleaning every three months, but towers in harsh environments may require more frequent cleaning. - What’s the difference between mechanical and chemical cleaning?
Mechanical cleaning removes debris and scale using scrubbing or pressure washing. Chemical cleaning uses specialized products to kill bacteria, control corrosion, and dissolve deposits. - Can I clean a cooling tower myself?
Basic checks can be done in-house, but deep cleaning requires trained professionals. At Pinnacle CTS, we follow OSHA safety standards and know how to handle chemicals correctly. - What chemicals are commonly used in cleaning cooling towers?
Typically, biocides are used to control bacteria, scale inhibitors to prevent deposits, and corrosion inhibitors to protect metal parts. - Does cleaning the cooling tower prevent Legionella?
Regular cleaning and water treatment lower the risk of Legionella by removing biofilm and keeping water chemistry balanced.
Final Thoughts
Regular cooling tower cleaning boosts system performance, extends its lifespan, and minimizes your energy costs. Follow these steps, from shutdown and draining to final inspections, to keep your cooling tower running at its best.
Of course, Pinnacle CTS is here to help you. We’re a leading cooling tower maintenance expert serving clients across the Greater Tri-State area. If you need help, call 732-570-9392 or get in touch with us online.
