Reduce Warm Water Temperature to Save Energy? Yes, but Beware of Microbiology.

Microbiology Testing Enables Safe Energy Saving

Energy saving is no doubt the hottest topic of this winter.

What can domestic households and commercial buildings do to contribute to energy saving? Reducing the temperature of the hot water supply seems to be a reasonable approach at first glance, as we often feel that hot water coming out of the tap is much warmer than we need. However, water professionals from DVGW, the German Technical and Scientific Association for Gas and Water, couldn’t fully agree. In a recently published paper of DVGW, Energie sparen beim warmen Trinkwasser – geht das?, experts warned about the consequentially increased risks of Legionella outbreaks, saying that hot water has to be hot enough, not just for the comfort of use, but also to limit the growth of bacteria and to keep residents safe.

Legionella bacteria are commonly found in water and pose the risk of Legionnaires' disease, a potentially fatal form of pneumonia. Legionella bacteria find ideal conditions for growth when temperatures are between 20-45°C and nutrients are available. The primary method used to control the risk from Legionella is water temperature control. For example, in the U.K. the Health and Safety Executive (HSE), Britain’s national regulator for workplace health and safety, recommends that hot water should be stored at a minimum of 60°C and distributed at 50°C or higher, while cold water systems should be maintained at a temperature of below 20°C. In Germany, the DVGW recommends a storage temperature of 55°C and disinfection at 60°C. Similarly, in the U.S., the Centers for Disease Control and Prevention (CDC) suggests to store hot water at temperatures above 60°C and to ensure that hot water in continuous circulation does not fall below 49°C (See more information on HSE’s Managing Legionella in hot and cold water systems, and on U.S. CDC’s Controlling Legionella in Potable Water Systems page). But the question of whether lower the temperature remains open for many water systems engineers and designers.

Controlling Legionella risks has never been easier.

At rqmicro, we have developed rapid and quantitative microbiology tests which enable safe and efficient energy saving. Our method allows quantifying Legionella in water systems in almost real-time and also distinguishes between live and dead Legionella cells providing facility managers and domestic households peace of mind. Traditional Legionella testing takes up to 15 days to get a result, and thus it cannot be used as a timely indicator of heating disinfection measures. Hot water has to be maintained constantly at a high temperature, at the cost of energy, just to avoid Legionella risks. Now thanks to rqmicro.COUNT, water system operators can:

   Easily detect Legionella on-site at any time and retrieve quantitative results in less than 2 hours after testing
  Receive test reports and outbreak alerts on mobile devices
  Evaluate the success of disinfection measures and treatment efficiency
  Get an overview of historical microbiological data on the rqmicro Cloud

Using the power of microbiology testing, rqmicro is protecting your health while enabling energy saving at the same time. 

Learn more about the rqmicro.COUNT and Legionella tests or contact us today. You can also view our video that shows how you can quantify Legionella in water with the rqmicro.COUNT. 

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