With 30 years’ experience in cooling tower cleaning and disinfection, Coolclean is trusted by leading Australian companies to provide a service that reduces Legionella risk, and optimises cooling tower performance.
Cooling towers are water and energy saving devices, which must be maintained correctly. There are two distinct areas of maintenance:
A. Water Treatment. Chemicals to control bacteria and water conditions. Conducted by water treatment companies.
B. Cleaning for public safety and performance optimisation. Conducted by Coolclean.
Performance Cleaning of cooling towers should be mandatory in every State in Australia. Quite a few quality water treatment companies and cooling tower service providers are providing performance-based cleaning to their clients, but unfortunately many are not.
Routine cleaning in many States is merely ‘disinfecting and cleaning out the basin’. Whereas Performance Cleaning reduces your Legionella risk, improves performance and possibly saves money at the same time.
The following critical cooling tower components must be cleaned on a regular basis (at least annually, but preferably every six months) to protect the public from Legionella bacteria. As part of our Performance Clean, Coolclean technicians work to a checklist to inspect every component, clean, disinfect and reassemble correctly – including difficult to access areas:
1. Drift eliminators. Drift eliminators help to stop the spread of the Legionella bacteria. ‘NO DRIFT MEANS NO LEGIONELLA’ leaving a cooling tower to infect the public. Drift eliminators MUST be inspected, kept clean and not damaged. Removal to clean is best practice.
2. Water distribution nozzles. Water nozzles and associated pipes/trays MUST be clean and free of debris so that treated cooling tower water can make full contact with all internal components. “YOU CANNOT KILL BACTERIA WITH CHEMICALS, if the chemicals are not in contact with the bacteria,” says Coolclean Managing Director Darren Driscoll. “If the water is not being distributed evenly across the fill pack, the coils, and the casing, then water treatment cannot be fully effective. The bacteria will live and breed where chemicals do not contact.”
3. Fill pack and coils. These are the heat exchange components. To cool effectively, fill pack and coils MUST be kept as clean as possible. It is critical that water runs over the surfaces freely without interference from dirt, scale and bacteria. Dirt in cooling tower fill pack is a breeding ground for bacteria.
4. Air intake louvers. These components stop water splash-out onto surfaces outside the cooling tower. Reducing water splash-out protects the environment. Updating air intake louvers to modern louvers with sunlight block out is a major improvement to assist the water treatment program as sunlight promotes bacteria and algae growth.
5. Other items to be cleaned. Casing, basin, fans and motor drives, hot water boxes, strainers, pumps, ball float valves, chemical dosing lines, the outside casing and the area surrounding a cooling tower.
Does your current cleaning include all of the above items? If you are unsure, the solution is to request photos as evidence that these components have been cleaned.
Performance Cleaning can also save money. Cooling towers that do not have Performance Cleans on a regular basis use excessive amounts of water, chemicals, electrical energy, and may contaminate the environment with excessive discharge called ‘drift’, which is higher than the AS 3666 discharge standards of 0.002%.
Under Government regulations, cooling towers must be disinfected, cleaned and re-disinfected at least twice per year as a minimum requirement. However, at present there are no industry control requirements in relation to what is actually done during the clean.
Our observation is that for many companies, their cleaning regime does not take care of critical components such as the cooling tower spray system, fill pack or drift eliminators. To ensure that cooling tower operation is efficient and safe, based on original design, as part of our standard cooling tower clean, Coolclean inspects every component for function, safety, reliability, and corrosion.
During our standard Performance Clean, we check all components that can impact the safety, performance or compliance of the unit.
Coolclean technicians inspect every component, clean, disinfect and reassemble correctly – including difficult to access areas. This includes the application of bio-dispersant and disinfectant, drain and isolate, followed by full pressure clean from top to bottom, with mechanical inspection, and four photos that are proof all access hatches were removed, drift eliminators accessed, removed and cleaned, water distribution cleaned, and top and bottom of fill pack inspected and cleaned. We work to a thorough checklist (as pictured, click image to view).
Could your cooling tower could be under performing? For example, blocked water nozzles (see video)