Legionnaires' disease is a serious disease caused by Legionella bacteria, which thrive in stagnant, warm water. Outbreaks of this disease have been associated with cooling towers, evaporative condensers, showers, faucets, hot tubs/whirlpool spas, and other sources of aerosolized water. Legionella bacteria favor a temperature of 25-42 C (77-108 F) for growth.
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People get Legionnaires' disease when they breathe in mist or vapor that has been contaminated with the bacteria.
Although some manufacturers set water heater thermostats at 140ºF, most households usually only require them set at 120ºF. Water heated at 140ºF also poses a safety hazard—scalding. However, if you have a dishwasher without a booster heater, it may require a water temperature within a range of 130ºF to 140ºF for optimum cleaning.
Reducing your water temperature to 120ºF also slows mineral buildup and corrosion in your water heater and pipes. This helps your water heater last longer and operate at its maximum efficiency.
[source: U.S. Department of Energy]
# 70 to 80 °C (158 to 176 °F): Disinfection range
# At 66 °C (151 °F): Legionellae die within 2 minutes
# At 60 °C (140 °F): Legionellae die within 32 minutes
# At 55 °C (131 °F): Legionellae die within 5 to 6 hours
# Above 50 °C (122 °F): They can survive but do not multiply
2-21-19 The EPA site has changed, this search link shows all the Legionella results::
If you expect exact math it is $200.00 per hour.
"Over a 4-day period, L. pneumophila grew more than 100-fold in the presence of D. discoideum (Fig. 1). The rate of growth between days 1 and 2 was rapid, with a doubling time of approximately 6 h, but slowed on days 2 to 4 post infection to a doubling time of approximately 16 h. "
A properly built solar hot water system ...
I understand that outside Europe there have been cases of Legionella linked to solar thermal.
I hope this is interesting.
Crazy question: why not just heat water on the stove and sponge bathe?
brice Moss wrote:
seeing this post makes me wonder if someone is creating an issue out of nothing cause my 'lectric water heater thingy has a sticker on the door by the temp controll advising me not to turn it up over 130 which I ignored of course cause I likes it at 195 cause I likes to be able to make tea outa the kitchen tap when I'm in a hurry