In any building that uses water, it is always important to consider the quality and safety of that water when evaluating how to keep up with maintenance. Hot water systems do not often come to mind when it comes to Legionella testing and prevention because most people assume that the hot temperature of the water is sufficient to deter the growth of this dangerous bacteria.
Preventing Legionella In Hot Water Systems
However, Legionella can still thrive and even multiply at temperatures hotter than most water systems are set at, and walking the fine line between keeping water hot enough to kill Legionella and avoiding scalding injuries is a balancing act. To prevent Legionella in your hot water system, consider the following steps.
Step 1: Testing
Of course, in order to get a better grasp on what your current Legionella situation is like, it is important that you test your water regularly. Understanding your load of Legionella and even what exact type it is can be useful information when determining how to proceed with disinfection and remediation.
Testing should be a regular part of your maintenance plan, and it should involve more than simply using a testing strip; take water from multiple points in your system and consider vulnerabilities in the hot water network such as dead legs. This will give you a more accurate picture of how Legionella might thrive in your system or avoid being killed by some of the next prevention tips.
Step 2: Cleaning and Disinfecting
Of course, any water system will begin to degrade over time as algae, scaling and other issues arise. Cleaning and disinfecting both your water and your system’s surfaces will remove vital safe havens and food sources from Legionella bacteria. If you are experiencing breakouts of algae or biofilms, these can not only pose a risk to your machinery but also provide safety for Legionella bacteria.
Cleaning can be done through filtration to capture larger particles in the water, but it may also involve actively cleaning and scrubbing the surfaces of basins and other parts of your hot water system, depending upon what type of equipment you are using. A skilled Legionella prevention professional can offer insight into what exactly will work for you.
Step 3: Chemical Shocking
Chemicals are often used to treat Legionella, and one of the most effective means of tackling the issue is a sudden high concentration of chlorine. Called hyperchlorination or chemical shock, the process involves using chlorine or other Halogens in concentrations higher than what is typically allowed for potable water for anywhere from one to 24 hours.
Cycling this high concentration through the system will kill Legionella, but it is important that you prepare not to use any water from the system during this time. After the procedure, water should be flushed from every access point for several minutes.
Step 4: High Temperature Flushing
In addition to chemicals, you can combat Legionella using hot water. Legionella typically thrive in temperatures between 77 degrees Fahrenheit and 108 degrees Fahrenheit—the range that is most comfortable for human use. However, they stop multiplying above 122 degrees and will begin to die around 131 degrees.
To disinfect a system, you may increase the temperature to 158 degrees Fahrenheit and open the access points so that water at this temperature flows through the system for as much as 20 minutes. Be aware that such hot water can cause severe injuries, such as near-instantaneous scalding and burns on the skin surface. This means that this type of Legionella prevention must be done when no users will need access to the water for some time.
Be aware, too, that not all types of heating equipment can raise the water temperature to this level; instantaneous heaters, for example, only heat water from cold to the desired temperature and so cannot typically be used for high-temperature flushing. However, if you have the time and safety protocols in place to perform high-temperature flushing from time to time, you can be sure that any Legionella exposed to the hot water will die.
Work With Our Legionella And Water Treatment Pros
If you are concerned about Legionella in your hot water system and are unsure how to proceed, or if you would like assistance carrying out a disinfection plan, it is important that you work with professionals who are experienced with Legionella prevention in hot water systems.
The pros at Legionella Compliance Solutions can examine your system and help you to understand which type of Legionella prevention will work best for your unique situation. Reach out to schedule an evaluation to discuss your options.