Hot Water Temp vs. Bacteria

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jackdashack

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I am always trying to find new sources where bacteria can lurk. I was reading today that a hot water tank that is kept low, say 120F, primarily to save costs, could allow the growth of bacteria. Okay sounds yuck! But bacteria already has a home on everyone of us and there's nothing we can do about it. So if you are not drinking hot water what's the harm in a little bacteria in the hot water tank?

So now to the cold water. If your municipality chlorinates the water isn't that enough. If you filter it isn't that enough yet? Is there still bacteria that could cause illness? Thanks much! jack ":-Dx
 
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You need 130F to kill legionella bacteria. Since you don't really flush out your hot water tank on a regular basis, the bottom can basically become a petrie dish. It grows in warm environments, treated or untreated water. We recently went through a big scare of it here in Halofax eith a few big apartment buildings on city supply
 
You need 130F to kill legionella bacteria. Since you don't really flush out your hot water tank on a regular basis, the bottom can basically become a petrie dish. It grows in warm environments, treated or untreated water. We recently went through a big scare of it here in Halofax eith a few big apartment buildings on city supply

Okay! I guess if the hot water has even a little bit coming through on the sink then entrance into humans is possible. Thanks! I will take action! Appreciate the answer. ":-Dx jack
 
There is a little thumbs up button at the bottom of every post, if you want to thank an individual post. Don't think there is any way to like a whole thread.
 
Okay! I guess if the hot water has even a little bit coming through on the sink then entrance into humans is possible. Thanks! I will take action! Appreciate the answer. ":-Dx jack

I have seen people make warm tea with the water from the hot water tap. I warn them that that is not a good practice.
The heat in the water heater destroys the chlorine in the hot water supply.
Chlorine in the cold water is a very effect in killing bacteria. It's the lead, other trace particles you should be worried about.
I was in the Mississippi delta area about 30 yrs ago and the water there has a really high sulfur content. :eek: they just use a lot of KOOLAID to mask the flavor.
 
Right off I see no place to mark solved, kudos, like or best answer?

I think some sights, the responders get paid for kudos and helpful answers.
Not here. We just get Love from those who hit that little I like button.
Sometimes a responder will invest some serious time answering a difficult question never to knowing if it actually helped the original poster.
 
I think some sights, the responders get paid for kudos and helpful answers.
Not here. We just get Love from those who hit that little I like button.
Sometimes a responder will invest some serious time answering a difficult question never to knowing if it actually helped the original poster.

That's why I ask as I am always aware of the time it takes. Sometimes it's not altogether apparent but in this case I looked right over the LIKE option. I think it's also good when a forum has a SOLVED option too so when looking up and down the question feed you know what's answered and what's not. Can save time. Even if there are no options for that I always send an appreciation note whether it actually helped me or not. That might seem hypocritical to some but I feel they gave time and their best shot and so deserve a thanks! :) So let me follow up on your last comment. Is 130F too hot in your estimation? I believe it was Matt30 above that said unless it's at least that hot it can be like a bacteria colony in the bottom of your heater. I have constant allergies. I have tried to investigate every aspect of my lifestyle, changing this and not eating that, etc. I just stumbled on this and took note that I keep my hot water tank very low on heat. You can hold your hand under it at the hottest. So I got to thinking. Maybe this bad bacteria is coming from my water supply. I wash dishes, brush my teeth in warm water from the hot water tank. The sponge is always in hot water. If there is bacteria from the tank it certainly has no problem getting into me. I do filter the cold but there is a lot of instances where the hot water can cross contaminate even though I don't directly drink it. :eek:
 
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the best investment I ever made ws $300 on an insta hot for the kitchn sink.

it sterilises using hot water and gives you instant boiled water. turn the burner on, fill the pot

set it on the burner, it boils.


Okay, I'll bite. What is an insta hot? :eek: Okay, Googled it and found one. The neighbor uses one.
 
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SOURCE- https://www.osha.gov/dts/osta/otm/otm_iii/otm_iii_7.html

OSHA TECHNICAL MANUAL - Legionnaires' Disease

III. Source Identification

A. Conditions that Promote Growth

1. pneumophila bacteria are widely distributed in water systems. They tend to grow in biofilms or slime on the surfaces of lakes, rivers and streams, and they are not eradicated by the chlorination used to purify domestic water systems. Low and even nondetectable levels of the organism can colonize a water source and grow to high concentrations under the right conditions.

Conditions that promote growth of the organism include heat, sediment, scale, and supporting (commensal) microflora in water. Common water organisms including algae, amoebae, and other bacteria appear to amplify Legionella growth by providing nutrients or harboring the organism. Because of its ability to remain viable in domestic water systems, it is capable of rapid multiplication under the proper conditions.

2.Water conditions that tend to promote the growth of Legionella include:

◾stagnation;

◾temperatures between 20° and 50°C (68° - 122°F) (The optimal growth range is 35° - 46°C [95° - 115°F]);

◾pH between 5.0 and 8.5
;

◾sediment that tends to promote growth of commensal microflora; and

◾micro-organisms including algae, flavobacteria, and Pseudomonas, which supply essential nutrients for growth of Legionella or harbor the organism (amoebae, protozoa).


B. Common Sources of Contaminated Water

1.Water sources that frequently provide optimal conditions for growth of the organisms include:

◾cooling towers, evaporative condensers, and fluid coolers that use evaporation to reject heat. These include many industrial processes that use water to remove excess heat;

◾domestic hot-water systems with water heaters that operate below 60°C (140°F) and deliver water to taps below 50°C (122°F);

◾humidifiers and decorative fountains that create a water spray and use water at temperatures favorable to growth;

◾spas and whirlpools;

◾dental water lines, which are frequently maintained at temperature above 20°C (68°F) and sometimes as warm as 37°C (98.6°F) for patient comfort; and

◾other sources including stagnant water in fire sprinkler systems and warm water for eye washes and safety showers.

2. Water stored below 20°C (68°F) is generally not a source for amplified L. pneumophila levels. However, high levels of bacteria have been measured in the water supplying ice machines. The source of amplification in this case was thought to be heat from the condenser coil of the ice maker to the cold water supply. However, no cases of Legionnaires' disease have been linked to consumption of ice made from contaminated water.

WH- Temp Mixing Valve _1.jpg
 
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Your more than welcome, but I ain't no PHD... :)

I am spoiled, lived on city water and sewage for years. Retired and moved up here on well and septic. To say it has been a learning experience...

What gets me about the bacterium living in the WH is even with tempered water to 140F, what happens if you put the WH on an energy savings schedule (cut off one element overnight), will the WH be able to maintain that 140F or would you have to uses an H2O2 injector for such periods (H2O2 will kill the bacterium)?

CDO IN W(BY GOD)V
 
I have constant allergies. I have tried to investigate every aspect of my lifestyle, changing this and not eating that, etc. :eek:
Don't get me wrong.
Just making a comment and not directed at you personally.
Often I shake my head when germ-a-phobics whine about touching a door nob or shopping baskets. But I understand.

Some people just do not have a very tolerant immune system.
Could be genetic, or just how they were raised.
I see a lot over protective mothers that won't let their kids play in the dirt.
Getting sick is part of how we build immunities to thing.
If one is getting sick often then I understand that one has to try to figure out why.
We had a friend who was constantly complaining of migraine head aches.
Turned out there was something in here carpet in the apartment she rented.
Replaced the carpet and the headaches subsided.

I am pretty healthy with the exception of maybe being 40 lbs over weight.
I stick my hands into a lot of nasty things.

I was cleaning a sewer line yesterday. Cable popped and splashed the crap in my face. :eek: Rule #1 keep your mouth close when cabling a drain.
I rarely ever get sick. I have never had a flu shot
Genetics??
Maybe cuz my mother told me to go outside and play??
Just Fortunate I guess.

off work early today so I'm just ranting.:cool:

Back to the water thing. They used to require water heaters to be set @ 140 F
to prevent Legionnairs Disease, but reduced it to 125 F do to sever scalding that can occur. at that higher temp.

According to article above 125 should be okay to prevent LD

2.Water conditions that tend to promote the growth of Legionella include:
◾temperatures between 20° and 50°C (68° - 122°F) (The optimal growth range is 35° - 46°C [95° - 115°F]);


We often set common Commercial heaters to 130 F that supply a multiple number of units


:cool::cool::cool::D
 
Being sanitary is much more important in our new THIRD WORLD COUNTRY Ayatollah O'Bama has introduced us to with all of these undocumented illegals and non-compliance with basic health codes (shots - quarantine) as was once done.

A few years ago, a BURGER KING in Germantown, MD had an undocumented worker who kept coughing. A few weeks went by and the store manager finally suggested that the work force leader take her to emergency. Turns out she had TB and was spitting it all over the food being served. It was in the paper. Did anyone care? Nope, back to business as usual.

We now see diseases that are either immune to antibiotics or there is simply no known treatment.

So even if you think you are above everyday illnesses, be prepared as an illegal has something special for you and is coming soon. If not disease then most likely lead poisoning... ;)
 

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