Between 55°C and 60°C, not more, not less.
Why is it important to have hot water at the correct
"In France there is a legal obligation that your domestic hot water production must be set between 55 ° C and 60 ° C. It is imperative to respect this minimum temperature for two reasons :
- avoid health risks related to the proliferation of bacteria and microbes that hide in pipes and hot water tanks. Below 55 ° C, there is a risk of developing legionellosis, a water contamination that can be fatal (between 1200 and 1500 cases are recorded each year in France). At 60 ° C, 90% of the bacteria die within 2 minutes.
- limit the appearance of scale in your pipes and appliances, which damage your installations.
On the other hand, it is not necessary to heat the water above 60 °to avoid the risk of burns. Requirements vary by country but in France a temperature limit at the points of draws (where you use water) is 50 ° C maximum in for example bathrroms and 60 ° C in the other rooms.
Think of installaing thermostatic mixing valves, which eliminate any risk of burns.
- avoid overconsumption of energy and water. No need to have water coming out of your boiler at 70 ° C while it will cool to use.
Finally, it is recommended that the control of the water temperature is as close as possible to the point of drawing and that your installation is not too far from your hot water production.
Conclusion, do not hesitate to take a look at your production of hot water and have a qualified professional re-adjust the temperature if necessary !