Home Page link

Running out of Hot Water

Home| Search | About
Login Password
Register Now! Lost Password?

Home Repair - - If it ain't broken, don't fix it. Otherwise look here. 

Page 1 of 4       1 2 3 > last >> Bookmark this page:  YahooMyWeb Yahoo!  Google Google  Windows Live Favorites Windows Live  del.icio.us del.icio.us  digg digg  Add to Netscape Netscape
Subject Author Date
Running out of Hot Water Paul of Dayton 02-01-2007
If you were  Registered and logged in, you could reply and use other advanced thread options
Posted by Paul of Dayton on February 1, 2007, 9:51 am


Hi Folks -

This one has me stumped. When we bought this house 5 years ago, we quickly
discovered it was easy to run out of hot water. I did the usual checks to
see if the WH was connected correctly and also checked each plumbing fixture
to see if a bad valve might be allowing the cold and hot to mix. I finally
chalked it up to on old 40gal gas heater full of gunk and turned the temp
up.

The heater finally died this summer so I replaced it with a 50gal unit with
a larger burner. I set it at the recommended setting and figured all would
be well. Lately, I find we are running out of hot water again. This
morning, one shower emptied it. It is burning correctly, just full of cold
water.

I bumped the temp up a bit but I really liked not burning my hands to a
cinder with hot water. There has to be something causing this but I am
stumped.

By the way, the old heater wasn't significantly heaver than the new one
after I emptied it.

Any ideas?

Thanks!

PoD

--



Never attribute to malice that which is adequately explained by stupidity.

-Hanlon's razor



Plumbing 468x60
Posted by on February 1, 2007, 10:15 am


wrote:
> Hi Folks -
>
> This one has me stumped. When we bought this house 5 years ago, we quickly
> discovered it was easy to run out of hot water. I did the usual checks to
> see if the WH was connected correctly and also checked each plumbing fixture
> to see if a bad valve might be allowing the cold and hot to mix. I finally
> chalked it up to on old 40gal gas heater full of gunk and turned the temp
> up.
>
> The heater finally died this summer so I replaced it with a 50gal unit with
> a larger burner. I set it at the recommended setting and figured all would
> be well. Lately, I find we are running out of hot water again. This
> morning, one shower emptied it. It is burning correctly, just full of cold
> water.
>
> I bumped the temp up a bit but I really liked not burning my hands to a
> cinder with hot water. There has to be something causing this but I am
> stumped.
>
> By the way, the old heater wasn't significantly heaver than the new one
> after I emptied it.
>
> Any ideas?
>
> Thanks!
>
> PoD
>
> --
>
> Never attribute to malice that which is adequately explained by stupidity.
>
> -Hanlon's razor


Very weird, unless of course, you are taking real long showers. With
2 water heaters, and one of them brand new, it would seem your idea of
the hot water somehow being cross connected with the cold is possible,
though it would seem unlikely.

I'd perform the following quick and easy test. Let the system sit
overnight. Then before any water is used, try opening just the cold
faucets one at a time, and let it flow for a min. Go check the hot
water pipe coming out of the WH a few feet from the unit. If it's
hot, you'll know that somehow the hot and cold are interconnected.

I'd also measure the temp of the water coming out of the hot faucet.
I think I have mine at about 130, which isn't real hot and I don't run
out here with a 40 gal unit.


Posted by BobK207 on February 1, 2007, 12:05 pm


wrote:
> Hi Folks -
>
> This one has me stumped. When we bought this house 5 years ago, we quickly
> discovered it was easy to run out of hot water. I did the usual checks to
> see if the WH was connected correctly and also checked each plumbing fixture
> to see if a bad valve might be allowing the cold and hot to mix. I finally
> chalked it up to on old 40gal gas heater full of gunk and turned the temp
> up.
>
> The heater finally died this summer so I replaced it with a 50gal unit with
> a larger burner. I set it at the recommended setting and figured all would
> be well. Lately, I find we are running out of hot water again. This
> morning, one shower emptied it. It is burning correctly, just full of cold
> water.
>
> I bumped the temp up a bit but I really liked not burning my hands to a
> cinder with hot water. There has to be something causing this but I am
> stumped.
>
> By the way, the old heater wasn't significantly heaver than the new one
> after I emptied it.
>
> Any ideas?
>
> Thanks!
>
> PoD
>
> --
>
> Never attribute to malice that which is adequately explained by stupidity.
>
> -Hanlon's razor

I think the key is:

.......Lately, I find we are running out of hot water again. This
morning, one shower emptied it. ...........

and

...... I set it at the recommended setting and figured all would be
well. .........

With a traditional tank style water heater there are couple of key
variables.

tank size, water heater recovery rate, water heater temperature
setting, hot water usage pattern & cold water feed temp

If the lack of hot water kinda went away last summer when you replaced
the old 40 with a 50 (does the new one have a better recovery rate?)
then I would guess that the problem came back because of a drop in
cold water feed temp in your area.

Plus mfr's suggest a "low" setting for energy savings & to avoid
liability wrt to scalding.

In my house the water heater is a small utility vault /
basement....access is via a small closet door & a stairway.....the
best I can do is a 40 but I made sure it had a better recovery rate
than average. It's in SoCal, so even in the winter the cold water is
usually about 60/65 at the coldest.

In colder areas of Ca (mountains) the cold water can get down to a
bone chilling 40/45F.....so cold that using cold water alone can be a
painful experience.

In addition as the cold water temp fails, one uses more hot water in a
shower situation........ in "normal" shower situtation closer to 1 to
1 mix will give you a decent shower temp. When your cold water temp
is COLD you wind up closer to a 2 to1 mix.


The solution most folks use is.....boost the water temp but that
increases the risk of scalding & increases energy loss to the
environment

The scald risk can be avoided with a tempering valve downstream of the
water heater.

As if there are not enough things to think about ........with
electric water heaters, there is a significant risk of Legionnaire's
disease bacteria being able to thrive at water temp setting of
120F...... even boosting to 140F doesn't eliminate the risk. Gas /
oil fired water heaters do not seem to have this problem.

cheers
Bob.


Posted by dpb on February 1, 2007, 2:27 pm


...

> As if there are not enough things to think about ........with
> electric water heaters, there is a significant risk of Legionnaire's
> disease bacteria being able to thrive at water temp setting of
> 120F...... even boosting to 140F doesn't eliminate the risk. Gas /
> oil fired water heaters do not seem to have this problem.
...

I can't find anything to substantiate the claim of electric vis a vis
gas being any different and in fact, the only real substantive place
that I saw it reported specifically states they cannot associate the
observed correlation w/ causation owing to confounding factors in the
study, not to mention it was a sample size of (3)...

"Although the Legionnaires' patients were more likely to have electric
than gas hot-water heaters, the finding was confounded with water
supply source -- that is, people with electric water heaters were also
more likely to have non-municipal water in their homes. Therefore, we
can't conclusively determine whether water heater type itself is
associated with Legionnaires' disease risk."
--http://researchnews.osu.edu/archive/legion.htm

I also found a brief quote from a report that indicates apparently a
followup study did not find any statistical correlation on the
electric water heater correlation. Here's a link and the blurb, but
am not IEEE member so couldn't read whole thing on line. DA(very)QGS
but didn't find the paper for further details.

"[h]ome electric water heaters were found not to be a. major risk
factor for Legionnaires' disease in a 2-year. study conducted recently
in Ohio. ..."
-- ieeexplore.ieee.org/iel1/39/9905/00469560.pdf?arnumber=469560

And, OSHA specifically notes while possible to acquire LBD from
inhaled mist in residential water systems, indications are the
probabilities are much less than for commercial systems and more
likely associated in the home w/ things such as whirlpools, etc.

"Q. Can my home water heater also be a source of LDB contamination?

A. Yes, but evidence indicates that smaller water systems such as
those used in homes are not as likely to be infected with LDB as
larger systems in workplaces and public buildings."

--http://www.osha.gov/dts/osta/otm/legionnaires/faq.html

So, I think you can stop worrying much over this one...

What I found does indicate that it pays to take care when doing
maintenance on plumbing systems and especially if on non-municipal
systems to be careful of general contamination issues in potable water
supplies. That, of course, is true for a myriad of other issues most
of which are more likely than LBD imo (coliform, etc., come to
mind...)


Posted by BobK207 on February 1, 2007, 6:10 pm


> ...
>
> > As if there are not enough things to think about ........with
> > electric water heaters, there is a significant risk of Legionnaire's
> > disease bacteria being able to thrive at water temp setting of
> > 120F...... even boosting to 140F doesn't eliminate the risk. Gas /
> > oil fired water heaters do not seem to have this problem.
>
> ...
>
> I can't find anything to substantiate the claim of electric vis a vis
> gas being any different and in fact, the only real substantive place
> that I saw it reported specifically states they cannot associate the
> observed correlation w/ causation owing to confounding factors in the
> study, not to mention it was a sample size of (3)...
>
> "Although the Legionnaires' patients were more likely to have electric
> than gas hot-water heaters, the finding was confounded with water
> supply source -- that is, people with electric water heaters were also
> more likely to have non-municipal water in their homes. Therefore, we
> can't conclusively determine whether water heater type itself is
> associated with Legionnaires' disease risk."
> --http://researchnews.osu.edu/archive/legion.htm
>
> I also found a brief quote from a report that indicates apparently a
> followup study did not find any statistical correlation on the
> electric water heater correlation. Here's a link and the blurb, but
> am not IEEE member so couldn't read whole thing on line. DA(very)QGS
> but didn't find the paper for further details.
>
> "[h]ome electric water heaters were found not to be a. major risk
> factor for Legionnaires' disease in a 2-year. study conducted recently
> in Ohio. ..."
> -- ieeexplore.ieee.org/iel1/39/9905/00469560.pdf?arnumber=469560
>
> And, OSHA specifically notes while possible to acquire LBD from
> inhaled mist in residential water systems, indications are the
> probabilities are much less than for commercial systems and more
> likely associated in the home w/ things such as whirlpools, etc.
>
> "Q. Can my home water heater also be a source of LDB contamination?
>
> A. Yes, but evidence indicates that smaller water systems such as
> those used in homes are not as likely to be infected with LDB as
> larger systems in workplaces and public buildings."
>
> --http://www.osha.gov/dts/osta/otm/legionnaires/faq.html
>
> So, I think you can stop worrying much over this one...
>
> What I found does indicate that it pays to take care when doing
> maintenance on plumbing systems and especially if on non-municipal
> systems to be careful of general contamination issues in potable water
> supplies. That, of course, is true for a myriad of other issues most
> of which are more likely than LBD imo (coliform, etc., come to
> mind...)


D-

here's the report I ran across

http://www.pulsus.com/infdis/15_01/leve_ed.htm

I should have posted with my earlier reply & I cannot vouch for the
reliability of the report but it looked like it came from a refereed
journal.

cheers
Bob

btw I don't worry about LBD or scalding there are too many more
important things closer to the top of that list


Page 1 of 4       1 2 3 > last >>
Similar ThreadsPosted
Continual water hammer when running hot water April 8, 2006, 1:04 pm
Hot water heater: running out of water too fast March 5, 2007, 9:03 am
Hot water heater running out of water January 6, 2008, 7:18 pm
slow running water January 7, 2006, 8:37 am
Water pump keeps running... April 13, 2006, 11:15 pm
Running a hot water line outside??? July 13, 2007, 7:29 am
Water pump won't stop running June 12, 2006, 12:30 pm
water pump running constantly June 17, 2006, 9:46 am
How can I dampen the sound of water running thru my pipes? June 15, 2005, 3:02 am
Ice water stops running in Hot Point refrigerator August 19, 2006, 9:28 pm

Contact Us | Privacy Policy

XML SitemapXML Sitemap