A friend has a house that came with two identical water
heaters hooked up in parallel. He doesn't need all the capacity,
so we turned one of them off and turned off the water going
into it. This was several years ago. The water heater was
about 4 years old at the time, it's now 7 years old.

Given that a tank has already had some service, what would
you guys do to try to keep the spare tank available for as long
as possible?

Leave it full of water?

Drain it?

My thought was that draining it would be worse, because
allowing air in, it would rust.......

I think you're right about the rust. Can you alternate them, every couple
months?

Not sure that makes any sense, but it's a thought.

Christopher A. Young
Learn more about Jesus
www.lds.org
..

wrote in message
...
A friend has a house that came with two identical water
heaters hooked up in parallel. He doesn't need all the capacity,
so we turned one of them off and turned off the water going
into it. This was several years ago. The water heater was
about 4 years old at the time, it's now 7 years old.

Given that a tank has already had some service, what would
you guys do to try to keep the spare tank available for as long
as possible?

Leave it full of water?

Drain it?

My thought was that draining it would be worse, because
allowing air in, it would rust.......

wrote in message
...
A friend has a house that came with two identical water
heaters hooked up in parallel. He doesn't need all the capacity,
so we turned one of them off and turned off the water going
into it. This was several years ago. The water heater was
about 4 years old at the time, it's now 7 years old.

Given that a tank has already had some service, what would
you guys do to try to keep the spare tank available for as long
as possible?

Leave it full of water?

Drain it?

My thought was that draining it would be worse, because
allowing air in, it would rust.......



Fill it with water, add a rust inhibitor?

As an aside, shouldn't two water heaters be hooked up in series?
Been meaning to post that to the group. The rcm peeple should have some
insights into both Qs.
--
EA

"Existential Angst" wrote:

wrote:
Given that a tank has already had some service, what would
you guys do to try to keep the spare tank available for as long
as possible?

Leave it full of water?

Drain it?

My thought was that draining it would be worse, because
allowing air in, it would rust.......



Fill it with water, add a rust inhibitor?


Drain it fully, blow out any remaining water with compressed air, purge
with heated dry air until you get no condensation whatsoever on a chilled
mirror and ideally finally purge with dry nitrogen and seal.

Most rust inhibitors are to some degree toxic so you dont want to use
them in the tank if it will be used for kitchen or bathroom hot water
unless they are specifcally marketed as non-toxic for food processig
plant. If you water-fill it, ideally use boiled water to reduce
dissolved oxygen.



--
Ian Malcolm. London, ENGLAND. (NEWSGROUP REPLY PREFERRED)
ianm[at]the[dash]malcolms[dot]freeserve[dot]co[dot]uk
[at]=@, [dash]=- & [dot]=. *Warning* HTML & 32K emails -- NUL

"Existential Angst" wrote in message
...

Given that a tank has already had some service, what would
you guys do to try to keep the spare tank available for as long
as possible?

Leave it full of water?

Drain it?

My thought was that draining it would be worse, because
allowing air in, it would rust.......
EA

I acquired a serviceable used electric water heater from a remodelling
project and mounted it horizontally in a close-fitted greenhouse box
as an unpressurized solar batch heater. After about 3-4 years the tank
started to spring small leaks on the cold bottom side which I patched
until I couldn't keep up.

Anything you put in it, like RV antifreeze, will be very tricky to
completely remove because the tanks are so hard to handle. The best
way I found was hanging it horizontal by a choker sling with the
heater holes on the bottom and spraying a hose in through them, but I
doubt I directly rinsed even half of the surface area and couldn't
touch anything absorbed into the crud in the vee groove around the
concave bottom end. Since the tank wasn't connected to my plumbing and
the water was only for laundry or car washing a little soap or LPS-3
in it didn't matter.

They can be difficult/expensive to dispose of unless you have a friend
in the scrap business. I traded two heaters for an old farm wagon
front axle.

On Feb 3, 9:53*am, "Existential Angst" wrote:
wrote in message

...





A friend has a house that came with two identical water
heaters hooked up in parallel. *He doesn't need all the capacity,
so we turned one of them off and turned off the water going
into it. *This was several years ago. *The water heater was
about 4 years old at the time, it's now 7 years old.

Given that a tank has already had some service, what would
you guys do to try to keep the spare tank available for as long
as possible?

Leave it full of water?

Drain it?

My thought was that draining it would be worse, because
allowing air in, it would rust.......

Fill it with water, add a rust inhibitor?

As an aside, shouldn't two water heaters be hooked up in series?
Been meaning to post that to the group. *The rcm peeple should have some
insights into both Qs.
--
EA- Hide quoted text -

- Show quoted text -

The issue of series vs parallel connection of dual water
heaters has been debated here a few times. AFAIK,
there wasn't any overwhelming advantage to either.
One difference would be that in parallel as soon as you've
drawn some amount of water, they are BOTH going to
fire, so you're getting 2X the heating sooner. With them
in series, the upstream one isn't going to fire until a lot
of the water has been drawn.

On the other hand, with them in series there is going to
be more hot water at a higher temp for longer due to
cold water not coming directly into the upstream tank.
In the grand scheme of things, it probably doesn't make
much difference.

wrote:
A friend has a house that came with two identical water
heaters hooked up in parallel. He doesn't need all the capacity,
so we turned one of them off and turned off the water going
into it. This was several years ago. The water heater was
about 4 years old at the time, it's now 7 years old.

Given that a tank has already had some service, what would
you guys do to try to keep the spare tank available for as long
as possible?

Leave it full of water?

Drain it?

My thought was that draining it would be worse, because
allowing air in, it would rust.......

I don't know the answer, but given the choice, I think I would drain it. My
thinking would be to drain it and leave the drain valve open to hopefully
let it completely dry out over time.

"Existential Angst" wrote in message
...
wrote in message
...
A friend has a house that came with two identical water
heaters hooked up in parallel. He doesn't need all the capacity,
so we turned one of them off and turned off the water going
into it. This was several years ago. The water heater was
about 4 years old at the time, it's now 7 years old.

Given that a tank has already had some service, what would
you guys do to try to keep the spare tank available for as long
as possible?

Leave it full of water?

Drain it?

My thought was that draining it would be worse, because
allowing air in, it would rust.......



Fill it with water, add a rust inhibitor?

As an aside, shouldn't two water heaters be hooked up in series?
Been meaning to post that to the group. The rcm peeple should have some
insights into both Qs.


Having a second tank that's unpowered, uninsulated, and plumbed in series so
that cold water passes through it first will reduce summertime AC and water
heating costs by naturally warming the inlet water up to room temp.

On 2/3/2013 9:11 AM, Ian Malcolm wrote:
"Existential Angst" wrote:

wrote:
Given that a tank has already had some service, what would
you guys do to try to keep the spare tank available for as long
as possible?

Leave it full of water?

Drain it?

My thought was that draining it would be worse, because
allowing air in, it would rust.......



Fill it with water, add a rust inhibitor?


Drain it fully, blow out any remaining water with compressed air, purge
with heated dry air until you get no condensation whatsoever on a chilled
mirror and ideally finally purge with dry nitrogen and seal.

Most rust inhibitors are to some degree toxic so you dont want to use
them in the tank if it will be used for kitchen or bathroom hot water
unless they are specifcally marketed as non-toxic for food processig
plant. If you water-fill it, ideally use boiled water to reduce
dissolved oxygen.

Dissolved oxygen? In H20?


--
Robert Allison
New Braunfels, TX

On 2/3/2013 8:44 AM, wrote:
A friend has a house that came with two identical water
heaters hooked up in parallel. He doesn't need all the capacity,
so we turned one of them off and turned off the water going
into it. This was several years ago. The water heater was
about 4 years old at the time, it's now 7 years old.

Given that a tank has already had some service, what would
you guys do to try to keep the spare tank available for as long
as possible?

Leave it full of water?

Drain it?

My thought was that draining it would be worse, because
allowing air in, it would rust.......


I would put them in series using the inactive heater as a tempering tank
but it would need to be drained on a schedule too as I think it could
catch some sediment from the incoming water. It would be available as a
ready backup and not that hard to bypass the other heater if/when it
failed. Assuming it a gas fired unit, it could be left on on a low
setting to keep the burners moisture and insect free. ^_^

TDD

On Feb 3, 1:05*pm, Robert Allison wrote:
On 2/3/2013 9:11 AM, Ian Malcolm wrote:





"Existential Angst" wrote:

wrote:
Given that a tank has already had some service, what would
you guys do to try to keep the spare tank available for as long
as possible?

Leave it full of water?

Drain it?

My thought was that draining it would be worse, because
allowing air in, it would rust.......

Fill it with water, add a rust inhibitor?

Drain it fully, blow out any remaining water with compressed air, purge
with heated dry air until you get no condensation whatsoever on a chilled
mirror and ideally finally purge with dry nitrogen and seal.

Most rust inhibitors are to some degree toxic so you dont want to use
them in the tank if it will be used for kitchen or bathroom hot water
unless they are specifcally marketed as non-toxic for food processig
plant. *If you water-fill it, ideally use boiled water to reduce
dissolved oxygen.

Dissolved oxygen? *In H20?

Well, sure. Fish, after all, couldn't survive without it.

But as for drying the tank out with heated dry air
and filling it with nitrogen, somehow I don't think that
is going to happen.....



--
Robert Allison
New Braunfels, TX- Hide quoted text -

- Show quoted text -

" wrote:

But as for drying the tank out with heated dry air
and filling it with nitrogen, somehow I don't think that
is going to happen.....


Not really a problem if you can adapt the nozzle of an electric hot air
gun to one of the ports of the tank and leave another port open. Don't
turn it up to its full paint-stripping setting! ;-)

I *KNOW* the dry nitrogen is unlikely to be convenient. . . .

--
Ian Malcolm. London, ENGLAND. (NEWSGROUP REPLY PREFERRED)
ianm[at]the[dash]malcolms[dot]freeserve[dot]co[dot]uk
[at]=@, [dash]=- & [dot]=. *Warning* HTML & 32K emails -- NUL

"Ian Malcolm" wrote in message
...
" wrote:

But as for drying the tank out with heated dry air
and filling it with nitrogen, somehow I don't think that
is going to happen.....


Not really a problem if you can adapt the nozzle of an electric hot air
gun to one of the ports of the tank and leave another port open. Don't
turn it up to its full paint-stripping setting! ;-)

I *KNOW* the dry nitrogen is unlikely to be convenient. . . .

Well, it is offered to auto buffs for whom nothing is too good for Nelly --
and to whom chemistry is still a mystery.... lol
http://www.quadratec.com/products/92...FUWo4AodIHoAIA
--
EA



--
Ian Malcolm. London, ENGLAND. (NEWSGROUP REPLY PREFERRED)
ianm[at]the[dash]malcolms[dot]freeserve[dot]co[dot]uk
[at]=@, [dash]=- & [dot]=. *Warning* HTML & 32K emails -- NUL

More accurately, dissolved air.

Christopher A. Young
Learn more about Jesus
www.lds.org
..

"Robert Allison" wrote in message
eb.com...
On 2/3/2013 9:11 AM, Ian Malcolm wrote:

Most rust inhibitors are to some degree toxic so you dont want to use
them in the tank if it will be used for kitchen or bathroom hot water
unless they are specifcally marketed as non-toxic for food processig
plant. If you water-fill it, ideally use boiled water to reduce
dissolved oxygen.

Dissolved oxygen? In H20?


--
Robert Allison
New Braunfels, TX

"Robert Allison" wrote in message
Dissolved oxygen? In H20?
Robert Allison
New Braunfels, TX

"Stormin Mormon" wrote in message
...
More accurately, dissolved air.
Christopher A. Young

Draw some hot water into a glass. The slowly disappearing milkiness is
tiny bubbles of air that comes out of solution when the pressure is
removed. Cold water holds more dissolved air than hot water.

wrote:
A friend has a house that came with two identical water
heaters hooked up in parallel. He doesn't need all the capacity,
so we turned one of them off and turned off the water going
into it. This was several years ago. The water heater was
about 4 years old at the time, it's now 7 years old.

Given that a tank has already had some service, what would
you guys do to try to keep the spare tank available for as long
as possible?

Leave it full of water?

Drain it?

My thought was that draining it would be worse, because
allowing air in, it would rust.......

2 thoughts"

Hot water furnaces and their piping don't corrode because the O2 that rusts them
gets used up, and the rusting stops, as I understand it.

As long as the anode is good, rust shouldn't happen, right?

Several points:

1. Robert Allison: Both oxygen and nitrogen from the air readily dissolve in ground water. As pointed out in a previous post, it's that dissolved oxygen in water that fish breathe to stay alive, even when the lake or river is covered in ice. Since MOST cities get their water from rivers or lakes, the tap water in most cities will contain dissolved oxygen. Some cities like Phoenix, Arizona and Las Vegas, Nevada get their water from an underground aquifer, and I don't know if that water contains any dissolved oxygen. Most tap water also contains some hardness ions (less so in "soft" water and moreso in "hard" water). It's the dissolved oxygen and hardness ions in tap water that make it a "not such a good idea" to change the water in your hot water heating system. Since it's that oxygen that causes rust on the inside of the iron boiler and iron piping, and the hardness ions that form scale on the hottest parts of the heating system (the boiler), you're better off to save the old oxygen depleted and ionically dead water you drain out of your heating system to do a repair, and siphon it back into the heating system after the repair is done, than to simply refill with new oxygen and ion rich water. No plumber would ever do that because you're paying him $90 per hour, and you're not going to want to see him carrying pails of water upstairs for that wage, or standing around not doing much of anything while the siphon is flowing to put that old water back in.

2. So far as the water heater goes, I would simply drain it. They say there is a "glass lined" steel tank inside the water heater, but this "glass lining" is just a porcelain enamel coating very similar to the enamel on a steel bathtub. So, if the water heater is only 4 years old, there shouldn't be any cracks in that enamel coating, and so the steel tank shouldn't rust any faster than a steel bathtub left empty. If you want to dry the tank out, simply unscrew both the drain valve and the pressure relief valve and use a vaccuum cleaner to suck the moist air out of the tank or blow fresh air in periodically.

Remember, cracks have to form in that porcelain enamel coating on the inside of the tank for the steel tank wall to come into contact with water and to start to rust along those crack lines. Otherwise, the water doesn't come into contact with the steel, and you won't have any rust. It's the repeated heating up and cooling down of that enamel coating that causes it to crack.

3. It's common to have two (or more) water heaters plumbed in parallel, but it's not common to see them plumbed in series. The reason for this is that in series, it's the first heater that does the lion's share of the work, and the second heater does very little work. The result is that you're going to be replacing that first heater as often as if it were working by itself. A. O. Smith says as much in their Technical Bulletin on series and parallel plumbing he
http://www.ho****er.com/lit/bulletin/bulletin64.pdf

(this web page edited the URL because of the character string "t-w-a-t" in A. O. Smith's web site.) Replace those stars with the correct letters, and you should find the right technical bulletin.

With two or more water heaters in parallel, the water inlet and outlet manifolds have to be designed so that the resistance to water flow through each heater is the same. This is typically done by making water inlet and outlet manifolds that provide the same resistance to flow for each water heater, like this:

On Feb 3, 10:55*pm, "Bob F" wrote:
wrote:
A friend has a house that came with two identical water
heaters hooked up in parallel. *He doesn't need all the capacity,
so we turned one of them off and turned off the water going
into it. *This was several years ago. *The water heater was
about 4 years old at the time, it's now 7 years old.

Given that a tank has already had some service, what would
you guys do to try to keep the spare tank available for as long
as possible?

Leave it full of water?

Drain it?

My thought was that draining it would be worse, because
allowing air in, it would rust.......

2 thoughts"

Hot water furnaces and their piping don't corrode because the O2 that rusts them
gets used up, and the rusting stops, as I understand it.

As long as the anode is good, rust shouldn't happen, right?- Hide quoted text -

- Show quoted text -

Rust and what the anode is there for are two seperate things.
Rust involves oxygen combining with iron. The sacrificial anode
involves two dissimilar metals in an electrolyte. Think about boats.
They use a similar approach, with zinc being used
as the sacrificial anode to protect the underwater metals. Zinc is
more reactive than bronze, stainless steel, etc so it comes off
instead.

In rec.crafts.metalworking PrecisionmachinisT wrote:

"Existential Angst" wrote in message
...
wrote in message
...
A friend has a house that came with two identical water
heaters hooked up in parallel. He doesn't need all the capacity,
so we turned one of them off and turned off the water going
into it. This was several years ago. The water heater was
about 4 years old at the time, it's now 7 years old.

Given that a tank has already had some service, what would
you guys do to try to keep the spare tank available for as long
as possible?

Leave it full of water?

Drain it?

My thought was that draining it would be worse, because
allowing air in, it would rust.......



Fill it with water, add a rust inhibitor?

As an aside, shouldn't two water heaters be hooked up in series?
Been meaning to post that to the group. The rcm peeple should have some
insights into both Qs.


Having a second tank that's unpowered, uninsulated, and plumbed in series so
that cold water passes through it first will reduce summertime AC and water
heating costs by naturally warming the inlet water up to room temp.

Other than skinning a trashed water heater, most of which are leaking
anyways, are there purpose made tanks for this use? I've been looking for
something along these lines to get "room temp" water for a photographic
darkroom where there's extended draw of water.

Anything homemade looking and attached to the water lines before the
backflow preventers might draw attention from the landlord or inspectors.
Just adding a waterheater-ish tank before the existing one would be the
easiest, as long as it draw no attention and won't burst over the weekend.

PrecisionmachinisT wrote:
"Existential Angst" wrote in message
...
wrote in message
...
A friend has a house that came with two identical water
heaters hooked up in parallel. He doesn't need all the capacity,
so we turned one of them off and turned off the water going
into it. This was several years ago. The water heater was
about 4 years old at the time, it's now 7 years old.

Given that a tank has already had some service, what would
you guys do to try to keep the spare tank available for as long
as possible?

Leave it full of water?

Drain it?

My thought was that draining it would be worse, because
allowing air in, it would rust.......



Fill it with water, add a rust inhibitor?

As an aside, shouldn't two water heaters be hooked up in series?
Been meaning to post that to the group. The rcm peeple should have
some insights into both Qs.

Having a second tank that's unpowered, uninsulated, and plumbed in
series so that cold water passes through it first will reduce
summertime AC and water heating costs by naturally warming the inlet
water up to room temp.

I am not sure, but I think that technically speaking that approach won't
save any money on energy costs. The reason is that for the water in the
first tank to be brought up to room temperature, it needs to draw its heat
energy from the room. So, it will cost that much more to heat the room
because some of the room heat is going toward heating the water in the first
tank. In other words, there is no free heat -- it either gets its heat from
being heated by at working hot water tank, or it gets its heat from the room
and that heat energy needs to be replaced by the heating system for the
room.

On Monday, February 4, 2013 2:56:03 PM UTC-5, TomR wrote:
PrecisionmachinisT wrote: "Existential Angst" wrote in message ... wrote in message ... A friend has a house that came with two identical water heaters hooked up in parallel. He doesn't need all the capacity, so we turned one of them off and turned off the water going into it. This was several years ago. The water heater was about 4 years old at the time, it's now 7 years old. Given that a tank has already had some service, what would you guys do to try to keep the spare tank available for as long as possible? Leave it full of water? Drain it? My thought was that draining it would be worse, because allowing air in, it would rust....... Fill it with water, add a rust inhibitor? As an aside, shouldn't two water heaters be hooked up in series? Been meaning to post that to the group. The rcm peeple should have some insights into both Qs. Having a second tank that's unpowered, uninsulated, and plumbed in series so that cold water passes through it first will reduce summertime AC and water heating costs by naturally warming the inlet water up to room temp. I am not sure, but I think that technically speaking that approach won't save any money on energy costs. The reason is that for the water in the first tank to be brought up to room temperature, it needs to draw its heat energy from the room. So, it will cost that much more to heat the room because some of the room heat is going toward heating the water in the first tank. In other words, there is no free heat -- it either gets its heat from being heated by at working hot water tank, or it gets its heat from the room and that heat energy needs to be replaced by the heating system for the room.

I believe he said "reduce summer time costs". And it does do that since ground water and city water are usually a lot cooler than summer air temps.

I run two wh in series with the 1st one on a 30amp switch in the hall. When I anticipate guests or otherwise needing extra hw I just turn it on.

On Feb 4, 3:53*pm, jamesgang wrote:
On Monday, February 4, 2013 2:56:03 PM UTC-5, TomR wrote:
PrecisionmachinisT wrote: "Existential Angst" wrote in message ... wrote in message ... A friend has a house that came with two identical water heaters hooked up in parallel. He doesn't need all the capacity, so we turned one of them off and turned off the water going into it. This was several years ago. The water heater was about 4 years old at the time, it's now 7 years old. Given that a tank has already had some service, what would you guys do to try to keep the spare tank available for as long as possible? Leave it full of water? Drain it? My thought was that draining it would be worse, because allowing air in, it would rust....... Fill it with water, add a rust inhibitor? As an aside, shouldn't two water heaters be hooked up in series? Been meaning to post that to the group. The rcm peeple should have some insights into both Qs. Having a second tank that's unpowered, uninsulated, and plumbed in series so that cold water passes through it first will reduce summertime AC and water heating costs by naturally warming the inlet water up to room temp. I am not sure, but I think that technically speaking that approach won't save any money on energy costs. The reason is that for the water in the first tank to be brought up to room temperature, it needs to draw its heat energy from the room. So, it will cost that much more to heat the room because some of the room heat is going toward heating the water in the first tank. In other words, there is no free heat -- it either gets its heat from being heated by at working hot water tank, or it gets its heat from the room and that heat energy needs to be replaced by the heating system for the room.

I believe he said "reduce summer time costs". *And it does do that since ground water and city water are usually a lot cooler than summer air temps.


But the proposed tank isn't going to be sitting outside in
the summer air. It's typically going to be in an unfinished
basement, or inside the living space. So, if you take city
water at 45F in winter and get it up to 60F in a basement,
I guess it will help some, but doubt it's worth the trouble.
In summer it would make even less difference, because
the incoming city water is going to be closer to basement
or living space temp.

For the guy asking if there are tanks suitable for the purpose,
that would seem to be any water tank that's suited for a
well pump. Preferably without a bladder inside, but that
could be removed. Might find one on craigslist....


I run two wh in series with the 1st one on a 30amp switch in the hall. *When I anticipate guests or otherwise needing extra hw I just turn it on..

jamesgang wrote:

I believe he said "reduce summer time costs". And it does do that
since ground water and city water are usually a lot cooler than
summer air temps.

You are correct. He wrote,

"Having a second tank that's unpowered, uninsulated, and plumbed in series
so
that cold water passes through it first will reduce summertime AC and water
heating costs by naturally warming the inlet water up to room temp."

I didn't catch that part - that he meant in the summertime with the AC on
etc.

On Mon, 4 Feb 2013 19:38:59 +0000 (UTC), Cydrome Leader
wrote:

In rec.crafts.metalworking PrecisionmachinisT wrote:

"Existential Angst" wrote in message
...
wrote in message
...
A friend has a house that came with two identical water
heaters hooked up in parallel. He doesn't need all the capacity,
so we turned one of them off and turned off the water going
into it. This was several years ago. The water heater was
about 4 years old at the time, it's now 7 years old.

Given that a tank has already had some service, what would
you guys do to try to keep the spare tank available for as long
as possible?

Leave it full of water?

Drain it?

My thought was that draining it would be worse, because
allowing air in, it would rust.......



Fill it with water, add a rust inhibitor?

As an aside, shouldn't two water heaters be hooked up in series?
Been meaning to post that to the group. The rcm peeple should have some
insights into both Qs.


Having a second tank that's unpowered, uninsulated, and plumbed in series so
that cold water passes through it first will reduce summertime AC and water
heating costs by naturally warming the inlet water up to room temp.

Other than skinning a trashed water heater, most of which are leaking
anyways, are there purpose made tanks for this use? I've been looking for
something along these lines to get "room temp" water for a photographic
darkroom where there's extended draw of water.

Anything homemade looking and attached to the water lines before the
backflow preventers might draw attention from the landlord or inspectors.
Just adding a waterheater-ish tank before the existing one would be the
easiest, as long as it draw no attention and won't burst over the weekend.


You could get a water heater that's being replaced before it bursts.
Just add a valve on its inlet side so there is no pressure on it when
it's not in use. It should last a long time without constant pressure
on it. If it does leak, you're right there.

"Cydrome Leader" wrote in message
...
In rec.crafts.metalworking PrecisionmachinisT
wrote:
"Existential Angst" wrote in message
...
wrote in message
...
..........
Other than skinning a trashed water heater, most of which are
leaking
anyways, are there purpose made tanks for this use? I've been
looking for
something along these lines to get "room temp" water for a
photographic
darkroom where there's extended draw of water.

I got nowhere by asking a plumbing supply house this question. The
owner thought it was a good idea but couldn't find an inexpensive tank
in his catalog.

The two best possibilities I can think of are a bladder tank for a
well and a water softener tank.
http://www.wwpp.com/products/flexcon...sure-tanks.htm
http://www.discoun****ersofteners.co...sin-tanks.html

Though they won't take much pressure, a blue plastic 55 gallon barrel
is a cheap option for the rinse water. I have one hung high in a shed
at the back of my large lot for brush fire protection. The larger bung
plug has a knockout for 3/4" NPT. ~5 PSI bulges the bottom enough to
make it tip over.
jsw

"TomR" wrote in message
...

I am not sure, but I think that technically speaking that approach
won't save any money on energy costs. The reason is that for the
water in the first tank to be brought up to room temperature, it
needs to draw its heat energy from the room. So, it will cost that
much more to heat the room because some of the room heat is going
toward heating the water in the first tank. In other words, there
is no free heat -- it either gets its heat from being heated by at
working hot water tank, or it gets its heat from the room and that
heat energy needs to be replaced by the heating system for the room.

"TomR" wrote in message
...
PrecisionmachinisT wrote:
"Existential Angst" wrote in message
...
wrote in message
...
A friend has a house that came with two identical water
heaters hooked up in parallel. He doesn't need all the capacity,
so we turned one of them off and turned off the water going
into it. This was several years ago. The water heater was
about 4 years old at the time, it's now 7 years old.

Given that a tank has already had some service, what would
you guys do to try to keep the spare tank available for as long
as possible?

Leave it full of water?

Drain it?

My thought was that draining it would be worse, because
allowing air in, it would rust.......



Fill it with water, add a rust inhibitor?

As an aside, shouldn't two water heaters be hooked up in series?
Been meaning to post that to the group. The rcm peeple should have
some insights into both Qs.

Having a second tank that's unpowered, uninsulated, and plumbed in
series so that cold water passes through it first will reduce
summertime AC and water heating costs by naturally warming the inlet
water up to room temp.

I am not sure, but I think that technically speaking that approach won't
save any money on energy costs. The reason is that for the water in the
first tank to be brought up to room temperature, it needs to draw its heat
energy from the room. So, it will cost that much more to heat the room

Which is why I said that energy savings occur during summertime through a
reduction in AC usage.

because some of the room heat is going toward heating the water in the
first tank. In other words, there is no free heat -- it either gets its
heat from being heated by at working hot water tank, or it gets its heat
from the room and that heat energy needs to be replaced by the heating
system for the room.

On Mon, 4 Feb 2013 19:38:59 +0000 (UTC)
Cydrome Leader wrote:

snip
Other than skinning a trashed water heater, most of which are leaking
anyways, are there purpose made tanks for this use? I've been looking for
something along these lines to get "room temp" water for a photographic
darkroom where there's extended draw of water.
snip

We have something like 150 ft of 1 inch black plastic water pipe in a
coil (maybe 3 ft in diameter), hanging on the wall downstairs before the
toilet supply. Does wonders in the summer time when they would sweat
otherwise. Used to have a galvanized water pressure tank for same years
ago but due to hard water it developed a lot of sediment. So far the
coiled up pipe seems to be working okay, maybe 20 years now.


--
Leon Fisk
Grand Rapids MI/Zone 5b
Remove no.spam for email

"Leon Fisk" wrote in message
...
On Mon, 4 Feb 2013 19:38:59 +0000 (UTC)
Cydrome Leader wrote:

snip
Other than skinning a trashed water heater, most of which are leaking
anyways, are there purpose made tanks for this use? I've been looking for
something along these lines to get "room temp" water for a photographic
darkroom where there's extended draw of water.
snip

We have something like 150 ft of 1 inch black plastic water pipe in a
coil (maybe 3 ft in diameter), hanging on the wall downstairs before the
toilet supply. Does wonders in the summer time when they would sweat
otherwise. Used to have a galvanized water pressure tank for same years
ago but due to hard water it developed a lot of sediment. So far the
coiled up pipe seems to be working okay, maybe 20 years now.

Putting that coil outside in the sun would be even better, in the summer.
Solar on the cheap....
Or in a black box, covered by glass..... really good solar, on the
cheap....

Toward the purpose-made tank Q: An old compressor tank, 30-50 gals? Or
smaller ones in series?
Even propane? Altho the fittings on propane are an experience to remove....
May want to paint the interior first.
--
EA




--
Leon Fisk
Grand Rapids MI/Zone 5b
Remove no.spam for email

wrote in message
...
On Feb 3, 10:55 pm, "Bob F" wrote:
wrote:
A friend has a house that came with two identical water
heaters hooked up in parallel. He doesn't need all the capacity,
so we turned one of them off and turned off the water going
into it. This was several years ago. The water heater was
about 4 years old at the time, it's now 7 years old.

Given that a tank has already had some service, what would
you guys do to try to keep the spare tank available for as long
as possible?

Leave it full of water?

Drain it?

My thought was that draining it would be worse, because
allowing air in, it would rust.......

2 thoughts"

Hot water furnaces and their piping don't corrode because the O2 that
rusts them
gets used up, and the rusting stops, as I understand it.

As long as the anode is good, rust shouldn't happen, right?- Hide quoted
text -

- Show quoted text -

Rust and what the anode is there for are two seperate things.
Rust involves oxygen combining with iron. The sacrificial anode
involves two dissimilar metals in an electrolyte
================================================== ==

A good observation, BUT the (dissolved) oxygen would/should combine with
sacrificial magnesium, zinc etc first, as well.

Magnesium, zinc, alum appear not to "rust" because the nature of those
oxides is *mechanically* stable, whereas iron oxides are not, constantly
exposing more fresh iron, ergo a deterioating process.
--
EA




. Think about boats.
They use a similar approach, with zinc being used
as the sacrificial anode to protect the underwater metals. Zinc is
more reactive than bronze, stainless steel, etc so it comes off
instead.

"jamesgang" wrote in message
...
On Monday, February 4, 2013 2:56:03 PM UTC-5, TomR wrote:
PrecisionmachinisT wrote: "Existential Angst"
wrote in message ...
wrote in message
...
A friend has a house that came with two identical water heaters
hooked up in parallel. He doesn't need all the capacity, so we turned
one of them off and turned off the water going into it. This was
several years ago. The water heater was about 4 years old at the time,
it's now 7 years old. Given that a tank has already had some
service, what would you guys do to try to keep the spare tank
available for as long as possible? Leave it full of water?
Drain it? My thought was that draining it would be worse,
because allowing air in, it would rust....... Fill it
with water, add a rust inhibitor? As an aside, shouldn't two water
heaters be hooked up in series? Been meaning to post that to the group.
The rcm peeple should have some insights into both Qs. Having a
second tank that's unpowered, uninsulated, and plumbed in series so that
cold water passes through it first will reduce summertime AC and water
heating costs by naturally warming the inlet water up to room temp. I am
not sure, but I think that technically speaking that approach won't save
any money on energy costs. The reason is that for the water in the first
tank to be brought up to room temperature, it needs to draw its heat
energy from the room. So, it will cost that much more to heat the room
because some of the room heat is going toward heating the water in the
first tank. In other words, there is no free heat -- it either gets its
heat from being heated by at working hot water tank, or it gets its heat
from the room and that heat energy needs to be replaced by the heating
system for the room.

I believe he said "reduce summer time costs". And it does do that since
ground water and city water are usually a lot cooler than summer air temps.

I run two wh in series with the 1st one on a 30amp switch in the hall. When
I anticipate guests or otherwise needing extra hw I just turn it on.
==============================================

Staged water heating.... what a neat idear!!
--
EA

On 2/5/2013 3:27 PM, Existential Angst wrote:
"Leon Fisk" wrote in message
...
On Mon, 4 Feb 2013 19:38:59 +0000 (UTC)
Cydrome Leader wrote:

snip
Other than skinning a trashed water heater, most of which are leaking
anyways, are there purpose made tanks for this use? I've been looking for
something along these lines to get "room temp" water for a photographic
darkroom where there's extended draw of water.
snip

We have something like 150 ft of 1 inch black plastic water pipe in a
coil (maybe 3 ft in diameter), hanging on the wall downstairs before the
toilet supply. Does wonders in the summer time when they would sweat
otherwise. Used to have a galvanized water pressure tank for same years
ago but due to hard water it developed a lot of sediment. So far the
coiled up pipe seems to be working okay, maybe 20 years now.

Putting that coil outside in the sun would be even better, in the summer.
Solar on the cheap....
Or in a black box, covered by glass..... really good solar, on the
cheap....
to get hot water in a toilet?

"chaniarts" wrote in message
...
On 2/5/2013 3:27 PM, Existential Angst wrote:
"Leon Fisk" wrote in message
...
On Mon, 4 Feb 2013 19:38:59 +0000 (UTC)
Cydrome Leader wrote:

snip
Other than skinning a trashed water heater, most of which are leaking
anyways, are there purpose made tanks for this use? I've been looking
for
something along these lines to get "room temp" water for a photographic
darkroom where there's extended draw of water.
snip

We have something like 150 ft of 1 inch black plastic water pipe in a
coil (maybe 3 ft in diameter), hanging on the wall downstairs before the
toilet supply. Does wonders in the summer time when they would sweat
otherwise. Used to have a galvanized water pressure tank for same years
ago but due to hard water it developed a lot of sediment. So far the
coiled up pipe seems to be working okay, maybe 20 years now.

Putting that coil outside in the sun would be even better, in the summer.
Solar on the cheap....
Or in a black box, covered by glass..... really good solar, on the
cheap....
to get hot water in a toilet?

Certainly..... who wants cold water splashing on their ass?? sheeesh.....
--
EA

On 2/5/2013 5:19 PM, chaniarts wrote:
On 2/5/2013 3:27 PM, Existential Angst wrote:
"Leon Fisk" wrote in message
...
On Mon, 4 Feb 2013 19:38:59 +0000 (UTC)
Cydrome Leader wrote:

snip
Other than skinning a trashed water heater, most of which are leaking
anyways, are there purpose made tanks for this use? I've been
looking for
something along these lines to get "room temp" water for a photographic
darkroom where there's extended draw of water.
snip

We have something like 150 ft of 1 inch black plastic water pipe in a
coil (maybe 3 ft in diameter), hanging on the wall downstairs before the
toilet supply. Does wonders in the summer time when they would sweat
otherwise. Used to have a galvanized water pressure tank for same years
ago but due to hard water it developed a lot of sediment. So far the
coiled up pipe seems to be working okay, maybe 20 years now.

Putting that coil outside in the sun would be even better, in the summer.
Solar on the cheap....
Or in a black box, covered by glass..... really good solar, on the
cheap....
to get hot water in a toilet?


There are actually mixing valves to mix hot water from the water heater
with the water supply to the toilet to keep the toilet tank from
sweating. ^_^

TDD

"The Daring Dufas" wrote in message
...
On 2/5/2013 5:19 PM, chaniarts wrote:
On 2/5/2013 3:27 PM, Existential Angst wrote:
"Leon Fisk" wrote in message
...
On Mon, 4 Feb 2013 19:38:59 +0000 (UTC)
Cydrome Leader wrote:

snip
Other than skinning a trashed water heater, most of which are leaking
anyways, are there purpose made tanks for this use? I've been
looking for
something along these lines to get "room temp" water for a
photographic
darkroom where there's extended draw of water.
snip

We have something like 150 ft of 1 inch black plastic water pipe in a
coil (maybe 3 ft in diameter), hanging on the wall downstairs before
the
toilet supply. Does wonders in the summer time when they would sweat
otherwise. Used to have a galvanized water pressure tank for same years
ago but due to hard water it developed a lot of sediment. So far the
coiled up pipe seems to be working okay, maybe 20 years now.

Putting that coil outside in the sun would be even better, in the
summer.
Solar on the cheap....
Or in a black box, covered by glass..... really good solar, on the
cheap....
to get hot water in a toilet?


There are actually mixing valves to mix hot water from the water heater
with the water supply to the toilet to keep the toilet tank from sweating.
^_^


Sounds like bidet temperature.... lol
--
EA



TDD

On 2/5/2013 8:36 PM, Existential Angst wrote:
"The Daring Dufas" wrote in message
...
On 2/5/2013 5:19 PM, chaniarts wrote:
On 2/5/2013 3:27 PM, Existential Angst wrote:
"Leon Fisk" wrote in message
...
On Mon, 4 Feb 2013 19:38:59 +0000 (UTC)
Cydrome Leader wrote:

snip
Other than skinning a trashed water heater, most of which are leaking
anyways, are there purpose made tanks for this use? I've been
looking for
something along these lines to get "room temp" water for a
photographic
darkroom where there's extended draw of water.
snip

We have something like 150 ft of 1 inch black plastic water pipe in a
coil (maybe 3 ft in diameter), hanging on the wall downstairs before
the
toilet supply. Does wonders in the summer time when they would sweat
otherwise. Used to have a galvanized water pressure tank for same years
ago but due to hard water it developed a lot of sediment. So far the
coiled up pipe seems to be working okay, maybe 20 years now.

Putting that coil outside in the sun would be even better, in the
summer.
Solar on the cheap....
Or in a black box, covered by glass..... really good solar, on the
cheap....
to get hot water in a toilet?


There are actually mixing valves to mix hot water from the water heater
with the water supply to the toilet to keep the toilet tank from sweating.
^_^


Sounds like bidet temperature.... lol


You mean one of those French made pet water fountains in a bathroom. ^_^

TDD

"The Daring Dufas" wrote in message
...
On 2/5/2013 8:36 PM, Existential Angst wrote:
"The Daring Dufas" wrote in message
...
On 2/5/2013 5:19 PM, chaniarts wrote:
On 2/5/2013 3:27 PM, Existential Angst wrote:
"Leon Fisk" wrote in message
...
On Mon, 4 Feb 2013 19:38:59 +0000 (UTC)
Cydrome Leader wrote:

snip
Other than skinning a trashed water heater, most of which are
leaking
anyways, are there purpose made tanks for this use? I've been
looking for
something along these lines to get "room temp" water for a
photographic
darkroom where there's extended draw of water.
snip

We have something like 150 ft of 1 inch black plastic water pipe in a
coil (maybe 3 ft in diameter), hanging on the wall downstairs before
the
toilet supply. Does wonders in the summer time when they would sweat
otherwise. Used to have a galvanized water pressure tank for same
years
ago but due to hard water it developed a lot of sediment. So far the
coiled up pipe seems to be working okay, maybe 20 years now.

Putting that coil outside in the sun would be even better, in the
summer.
Solar on the cheap....
Or in a black box, covered by glass..... really good solar, on the
cheap....
to get hot water in a toilet?


There are actually mixing valves to mix hot water from the water heater
with the water supply to the toilet to keep the toilet tank from
sweating.
^_^


Sounds like bidet temperature.... lol


You mean one of those French made pet water fountains in a bathroom. ^_^

Also a hillbilly water fountain/emergency eyewash....
A few here.... George, Attila, JoeBoi -- will proly further misconstrue it,
and use it to pressurize demselves, shooting off the bidet like a water
rocket.... proly up to the stratosphere.
--
EA



TDD

The Daring Dufas wrote:

Existential Angst wrote:

Sounds like bidet temperature.... lol


You mean one of those French made pet water fountains in a bathroom. ^_^


Shouldn't you use ice water for those?

On 2/6/2013 6:00 AM, Michael A. Terrell wrote:

The Daring Dufas wrote:

Existential Angst wrote:

Sounds like bidet temperature.... lol


You mean one of those French made pet water fountains in a bathroom. ^_^


Shouldn't you use ice water for those?


I suppose it depends on whether or not your dog likes ice water? O_o

TDD

The Daring Dufas wrote:

On 2/6/2013 6:00 AM, Michael A. Terrell wrote:

The Daring Dufas wrote:

Existential Angst wrote:

Sounds like bidet temperature.... lol


You mean one of those French made pet water fountains in a bathroom. ^_^


Shouldn't you use ice water for those?


I suppose it depends on whether or not your dog likes ice water? O_o


You've never seen a dog go berserk over ice cubes? Or give you a
dirty look, because all the ice has melted & the water in their bowl is
warm?