On Saturday, June 25, 2011 6:49:21 PM UTC-4, unk...@googlegroups.com wrote:
> On Sat, 25 Jun 2011 13:30:59 -0700 (PDT), Jerry Avins <j...@ieee.org>
> wrote:
>
> >On Jun 25, 2:35�pm, "Tom Del Rosso" <td...@verizon.net.invalid> wrote:
> >> Julie Bove wrote:
> >> > Polly Esther wrote:
> >> > > Just in case you were thinking of using water from your hot water
> >> > > tank for cooking because it 'may' be faster, I'm not so sure that's
> >> > > a good idea. Polly
> >>
> >> > I know they used to say this because lead was more likely to leach
> >> > from the pipes. �But if you have a house with PVC pipes likeI do,
> >> > this probably isn't true.
> >>
> >> I don't care about the pipes. �The tank is filled with mostly stagnant
> >> water.

> >
> >Stagnant? Is that a joke? How long since the water in the mains (or
> >well) saw free air and the light of day? Stagnant water is what people
> >pay a dollar a bottle for.

>
> But he's correct. Hot water tanks contain stagnated water towards the
> bottom of the tank, it rarely moves or gets exchanged, and since heat
> rises the water at the bottom is rather tepid, perfect for incubating
> bacteria...


You are evidently unaware of how a water heater is constructed. Incoming cold water is delivered to the bottom of the tank through an internal pipe called a dip tube, and heated water is drawn off from the top. Nowadays, hot water tanks are insulated, but when I was a kid one could tell how much of the water was hot by feeling the side of the tank. The transition from hot to cold occupied a zone of about 8 inches, the water being nearly uniformlyhot above the transition and unheated below it.

http://tinyurl.com/3foegst

Jerry
--
Engineering is the art of making what you want from things you can get.