We recently bought a new house that has dual 50-gallon electric water
heaters. Each heater has a single 5500 Watt heating element.

The 'problem' is that there are only two of us living in the house, and we
very likely don't need 100 gallons of hot water standing by. The electric
bill is out of control, and we're thinking the dual water heaters are a
chunk of that.

The two heaters appear to be plumbed in parallel rather than series. Can I
turn off the cold water inlet valve on one heater and unplug it to save some
electric power? Do I need to drain the heater that I won't be using? Should
I take the extra step of connecting the inlet pipe to the outlet pipe, (on
the plumbing side, not the heater side), in order to completely bypass that
heater? What else might I be missing?

On 06/03/2014 12:15 AM, Jim Joyce wrote:

We recently bought a new house that has dual 50-gallon electric water
heaters. Each heater has a single 5500 Watt heating element.

The 'problem' is that there are only two of us living in the house, and we
very likely don't need 100 gallons of hot water standing by. The electric
bill is out of control, and we're thinking the dual water heaters are a
chunk of that.

The two heaters appear to be plumbed in parallel rather than series. Can I
turn off the cold water inlet valve on one heater and unplug it to save some
electric power? Do I need to drain the heater that I won't be using? Should
I take the extra step of connecting the inlet pipe to the outlet pipe, (on
the plumbing side, not the heater side), in order to completely bypass that
heater? What else might I be missing?

I'd test running on one heater for a week or so.
Then I'd drain and remove the unused one.

On Tue, 03 Jun 2014 04:34:27 -0400, Jimbo wrote:

On 06/03/2014 12:15 AM, Jim Joyce wrote:


The two heaters appear to be plumbed in parallel rather than series. Can I
turn off the cold water inlet valve on one heater and unplug it to save some
electric power? Do I need to drain the heater that I won't be using? Should
I take the extra step of connecting the inlet pipe to the outlet pipe, (on
the plumbing side, not the heater side), in order to completely bypass that
heater? What else might I be missing?

I'd test running on one heater for a week or so.
Then I'd drain and remove the unused one.

I've flush it, drain it, and shut the valves off. Kill the power, of
course. If the space is not a problem, you'd have a spare ready to go
when the other one fails.

On 06/03/2014 04:56 AM, Ed Pawlowski wrote:
On Tue, 03 Jun 2014 04:34:27 -0400, Jimbo wrote:

On 06/03/2014 12:15 AM, Jim Joyce wrote:


The two heaters appear to be plumbed in parallel rather than series. Can I
turn off the cold water inlet valve on one heater and unplug it to save some
electric power? Do I need to drain the heater that I won't be using? Should
I take the extra step of connecting the inlet pipe to the outlet pipe, (on
the plumbing side, not the heater side), in order to completely bypass that
heater? What else might I be missing?

I'd test running on one heater for a week or so.
Then I'd drain and remove the unused one.

I've flush it, drain it, and shut the valves off. Kill the power, of
course. If the space is not a problem, you'd have a spare ready to go
when the other one fails.




I agree that it would be a good idea to take one out of service but I
wonder if it would be better not to drain it. The minerals in the water
could solidify and clog the heater.

I'd probably rotate their use every six months or so.

On Tuesday, June 3, 2014 12:15:57 AM UTC-4, Jim Joyce wrote:
We recently bought a new house that has dual 50-gallon electric water

heaters. Each heater has a single 5500 Watt heating element.



The 'problem' is that there are only two of us living in the house, and we

very likely don't need 100 gallons of hot water standing by. The electric

bill is out of control, and we're thinking the dual water heaters are a

chunk of that.



The two heaters appear to be plumbed in parallel rather than series. Can I

turn off the cold water inlet valve on one heater and unplug it to save some

electric power? Do I need to drain the heater that I won't be using? Should

I take the extra step of connecting the inlet pipe to the outlet pipe, (on

the plumbing side, not the heater side), in order to completely bypass that

heater? What else might I be missing?


Unplug it? Maybe it's on a plug, but all the electric WH's I've
seen were wired in. Nat gas ones that have a blower, those are on cords.
If there is no plug, maybe you can open the breaker, but not sure if
they would have separate breakers or be on one larger breaker

But if you want to disable one, I would just do what you suggested,
turn off the water supply and electric. I've done that with nat gas
ones that were in parallel where the house didn't really need two.
One problem though is that you only have 5500W? That's small for a
50 gallon, the recovery time is going to be slow, and with only one,
you might run out at times, but you can try it and see.

From a longevity standpoint, you might be better off fully draining
it, leaving connections open so it could dry out. Not sure what effect
that would have in terms of keeping it good for future use versus
leaving it full of water.

It will save some money, but I doubt it's the source of much of your
bill. Whether you have one or two, it's going to take the same amount
of electricity to heat the water you use. The only thing you'll save
is the standby losses on the second tank. Electric ones are fully
insulated, have no flue up the middle, so I doubt it's going to make
much difference, but it will help.

On Tuesday, June 3, 2014 9:03:08 AM UTC-4, trader_4 wrote:
On Tuesday, June 3, 2014 12:15:57 AM UTC-4, Jim Joyce wrote:

We recently bought a new house that has dual 50-gallon electric water



heaters. Each heater has a single 5500 Watt heating element.







The 'problem' is that there are only two of us living in the house, and we



very likely don't need 100 gallons of hot water standing by. The electric



bill is out of control, and we're thinking the dual water heaters are a



chunk of that.







The two heaters appear to be plumbed in parallel rather than series. Can I



turn off the cold water inlet valve on one heater and unplug it to save some



electric power? Do I need to drain the heater that I won't be using? Should



I take the extra step of connecting the inlet pipe to the outlet pipe, (on



the plumbing side, not the heater side), in order to completely bypass that



heater? What else might I be missing?





Unplug it? Maybe it's on a plug, but all the electric WH's I've

seen were wired in. Nat gas ones that have a blower, those are on cords.

If there is no plug, maybe you can open the breaker, but not sure if

they would have separate breakers or be on one larger breaker



But if you want to disable one, I would just do what you suggested,

turn off the water supply and electric. I've done that with nat gas

ones that were in parallel where the house didn't really need two.

One problem though is that you only have 5500W? That's small for a

50 gallon, the recovery time is going to be slow, and with only one,

you might run out at times, but you can try it and see.



From a longevity standpoint, you might be better off fully draining

it, leaving connections open so it could dry out. Not sure what effect

that would have in terms of keeping it good for future use versus

leaving it full of water.



It will save some money, but I doubt it's the source of much of your

bill. Whether you have one or two, it's going to take the same amount

of electricity to heat the water you use. The only thing you'll save

is the standby losses on the second tank. Electric ones are fully

insulated, have no flue up the middle, so I doubt it's going to make

much difference, but it will help.

You'd be surprised. We had a vacation house and I put a 30amp double pole switch in the hall to turn off the water heater when we were not there. Knocked 30-40 bucks off the bill.

On Tue, 03 Jun 2014 04:34:27 -0400, Jimbo wrote:

On 06/03/2014 12:15 AM, Jim Joyce wrote:

We recently bought a new house that has dual 50-gallon electric water
heaters. Each heater has a single 5500 Watt heating element.

The 'problem' is that there are only two of us living in the house, and we
very likely don't need 100 gallons of hot water standing by. The electric
bill is out of control, and we're thinking the dual water heaters are a
chunk of that.

The two heaters appear to be plumbed in parallel rather than series. Can I
turn off the cold water inlet valve on one heater and unplug it to save some
electric power? Do I need to drain the heater that I won't be using? Should
I take the extra step of connecting the inlet pipe to the outlet pipe, (on
the plumbing side, not the heater side), in order to completely bypass that
heater? What else might I be missing?

I'd test running on one heater for a week or so.
Then I'd drain and remove the unused one.

Thanks, Jimbo. The two heaters are in a closet in a corner of the garage, so
I like the idea of leaving the second one there for future use, or rotating
their use, etc.

On Tue, 03 Jun 2014 05:56:12 -0400, Ed Pawlowski wrote:

On Tue, 03 Jun 2014 04:34:27 -0400, Jimbo wrote:

On 06/03/2014 12:15 AM, Jim Joyce wrote:


The two heaters appear to be plumbed in parallel rather than series. Can I
turn off the cold water inlet valve on one heater and unplug it to save some
electric power? Do I need to drain the heater that I won't be using? Should
I take the extra step of connecting the inlet pipe to the outlet pipe, (on
the plumbing side, not the heater side), in order to completely bypass that
heater? What else might I be missing?

I'd test running on one heater for a week or so.
Then I'd drain and remove the unused one.

I've flush it, drain it, and shut the valves off. Kill the power, of
course. If the space is not a problem, you'd have a spare ready to go
when the other one fails.

Right, space is not a problem. I like your approach. Thanks.

On Tue, 03 Jun 2014 07:35:03 -0500, philo* wrote:

On 06/03/2014 04:56 AM, Ed Pawlowski wrote:
On Tue, 03 Jun 2014 04:34:27 -0400, Jimbo wrote:

On 06/03/2014 12:15 AM, Jim Joyce wrote:


The two heaters appear to be plumbed in parallel rather than series. Can I
turn off the cold water inlet valve on one heater and unplug it to save some
electric power? Do I need to drain the heater that I won't be using? Should
I take the extra step of connecting the inlet pipe to the outlet pipe, (on
the plumbing side, not the heater side), in order to completely bypass that
heater? What else might I be missing?

I'd test running on one heater for a week or so.
Then I'd drain and remove the unused one.

I've flush it, drain it, and shut the valves off. Kill the power, of
course. If the space is not a problem, you'd have a spare ready to go
when the other one fails.




I agree that it would be a good idea to take one out of service but I
wonder if it would be better not to drain it. The minerals in the water
could solidify and clog the heater.

Just a few weeks ago we flushed both heaters, which probably hadn't been
done since the house was built in 2006. (We just bought the house in August
of last year.) Wow, what a load of mineral deposits! Milky white water and
an endless supply of 'chunks'.

I'd probably rotate their use every six months or so.

That would be easy since both are in a cabinet in a corner of the garage.
Thanks.

On Tue, 3 Jun 2014 06:03:08 -0700 (PDT), trader_4
wrote:

Unplug it? Maybe it's on a plug, but all the electric WH's I've
seen were wired in.

Each of these have a standard 240V plug, the same type as my clothes dryer,
and they share a breaker in the electrical panel. I flipped the breaker off
and unplugged them when I was flushing out the mineral build-up.

But if you want to disable one, I would just do what you suggested,
turn off the water supply and electric. I've done that with nat gas
ones that were in parallel where the house didn't really need two.
One problem though is that you only have 5500W? That's small for a
50 gallon, the recovery time is going to be slow, and with only one,
you might run out at times, but you can try it and see.

Our last house was nearly the same size and had a single 50-gal heater, but
that heater had both a lower element and an upper element. I'm not sure of
their respective wattages.

From a longevity standpoint, you might be better off fully draining
it, leaving connections open so it could dry out. Not sure what effect
that would have in terms of keeping it good for future use versus
leaving it full of water.

It will save some money, but I doubt it's the source of much of your
bill. Whether you have one or two, it's going to take the same amount
of electricity to heat the water you use. The only thing you'll save
is the standby losses on the second tank. Electric ones are fully
insulated, have no flue up the middle, so I doubt it's going to make
much difference, but it will help.

When we moved in, we didn't have *hot* water, which eventually prompted me
to check the heaters. One's overtemp limit switch was tripped, so we had
been running on one heater with the second one providing unheated water.
When I reset the overtemp limit switch, the following month the electric
bill went from $78 to $142. I'm sure there were other things involved, but
I'm hoping the biggest chunk of that jump was the second heater.

Anyway, thanks everyone. For now, I'll flip the cold water inlet valve off
and unplug one of the heaters. We'll see how things go, as far as
temperature and supply. I don't think I'll drain it for now, in case I
decide to rotate the heaters every X months.

On 06/03/2014 05:42 PM, Jim Joyce wrote:
On Tu

I agree that it would be a good idea to take one out of service but I
wonder if it would be better not to drain it. The minerals in the water
could solidify and clog the heater.

Just a few weeks ago we flushed both heaters, which probably hadn't been
done since the house was built in 2006. (We just bought the house in August
of last year.) Wow, what a load of mineral deposits! Milky white water and
an endless supply of 'chunks'.

I'd probably rotate their use every six months or so.

That would be easy since both are in a cabinet in a corner of the garage.
Thanks.



The reason I suggested rotation :


I rarely use the hot water on my washer but needed to do a load the
other day using hot.

The pipe was clogged.

On Tuesday, June 3, 2014 4:47:13 PM UTC-4, jamesgang wrote:
On Tuesday, June 3, 2014 9:03:08 AM UTC-4, trader_4 wrote:

On Tuesday, June 3, 2014 12:15:57 AM UTC-4, Jim Joyce wrote:



We recently bought a new house that has dual 50-gallon electric water







heaters. Each heater has a single 5500 Watt heating element.















The 'problem' is that there are only two of us living in the house, and we







very likely don't need 100 gallons of hot water standing by. The electric







bill is out of control, and we're thinking the dual water heaters are a







chunk of that.















The two heaters appear to be plumbed in parallel rather than series. Can I







turn off the cold water inlet valve on one heater and unplug it to save some







electric power? Do I need to drain the heater that I won't be using? Should







I take the extra step of connecting the inlet pipe to the outlet pipe, (on







the plumbing side, not the heater side), in order to completely bypass that







heater? What else might I be missing?











Unplug it? Maybe it's on a plug, but all the electric WH's I've



seen were wired in. Nat gas ones that have a blower, those are on cords.



If there is no plug, maybe you can open the breaker, but not sure if



they would have separate breakers or be on one larger breaker







But if you want to disable one, I would just do what you suggested,



turn off the water supply and electric. I've done that with nat gas



ones that were in parallel where the house didn't really need two.



One problem though is that you only have 5500W? That's small for a



50 gallon, the recovery time is going to be slow, and with only one,



you might run out at times, but you can try it and see.







From a longevity standpoint, you might be better off fully draining



it, leaving connections open so it could dry out. Not sure what effect



that would have in terms of keeping it good for future use versus



leaving it full of water.







It will save some money, but I doubt it's the source of much of your



bill. Whether you have one or two, it's going to take the same amount



of electricity to heat the water you use. The only thing you'll save



is the standby losses on the second tank. Electric ones are fully



insulated, have no flue up the middle, so I doubt it's going to make



much difference, but it will help.



You'd be surprised. We had a vacation house and I put a 30amp double pole switch in the hall to turn off the water heater when we were not there. Knocked 30-40 bucks off the bill.

I guess it's possible it could be in that range. I was winging it off
the fact that the standby from my nat gas WH can't amount to much
because in the summer, my whole nat gas bill is $17 a month. I
was figuring most of that was for actual water heating that was used.
But maybe most of it is from standy, I really have no way of knowing
If say $10 was from standby and
then you factor in that electric costs about 2.7 times as much, that
would give you $27 for an electric one, which is near your numbers.
Whatever it is, if
the OP doesn't need that extra tank, turning it off will make a
worthwhile difference.

On Tue, 03 Jun 2014 05:56:12 -0400, Ed Pawlowski wrote:

On Tue, 03 Jun 2014 04:34:27 -0400, Jimbo wrote:

On 06/03/2014 12:15 AM, Jim Joyce wrote:


The two heaters appear to be plumbed in parallel rather than series. Can I
turn off the cold water inlet valve on one heater and unplug it to save some
electric power? Do I need to drain the heater that I won't be using? Should
I take the extra step of connecting the inlet pipe to the outlet pipe, (on
the plumbing side, not the heater side), in order to completely bypass that
heater? What else might I be missing?

I'd test running on one heater for a week or so.
Then I'd drain and remove the unused one.

I've flush it, drain it, and shut the valves off. Kill the power, of
course. If the space is not a problem, you'd have a spare ready to go
when the other one fails.

Absoluely don't remove a good WH. Besides the one in use failing, what
if four people drop in to visit you, your family or refugees from a fire
or flood? Even if they live in a camper outside, you might want them to
take hot showers inside.

On Tue, 03 Jun 2014 17:54:52 -0500, Jim Joyce wrote:

On Tue, 3 Jun 2014 06:03:08 -0700 (PDT), trader_4
wrote:

Unplug it? Maybe it's on a plug, but all the electric WH's I've
seen were wired in.

Each of these have a standard 240V plug, the same type as my clothes dryer,

Plainly, the installer envisioned running only one of them some times.

and they share a breaker in the electrical panel. I flipped the breaker off
and unplugged them when I was flushing out the mineral build-up.

But if you want to disable one, I would just do what you suggested,
turn off the water supply and electric. I've done that with nat gas
ones that were in parallel where the house didn't really need two.
One problem though is that you only have 5500W? That's small for a
50 gallon, the recovery time is going to be slow, and with only one,
you might run out at times, but you can try it and see.

Our last house was nearly the same size and had a single 50-gal heater, but
that heater had both a lower element and an upper element. I'm not sure of
their respective wattages.


When we moved in, we didn't have *hot* water, which eventually prompted me
to check the heaters. One's overtemp limit switch was tripped, so we had
been running on one heater with the second one providing unheated water.
When I reset the overtemp limit switch, the following month the electric
bill went from $78 to $142. I'm sure there were other things involved, but

Wow!!!!! I would have thought the difference would be very little.
Please post back with next month's bill, and how many days in each
billing month.

Maybe you have a dripping hot water faucet.


I'm hoping the biggest chunk of that jump was the second heater.

Anyway, thanks everyone. For now, I'll flip the cold water inlet valve off
and unplug one of the heaters. We'll see how things go, as far as
temperature and supply. I don't think I'll drain it for now, in case I
decide to rotate the heaters every X months.

Jim:
It's actually a good idea to have two water heaters plumbed in series. That way, if and when one water heater kicks the bucket, you can simply switch over to the other water heater while the first one is being replaced.

Also, you can use that second water heater while doing maintenance on the first heater, like replacing the anode in it. That way you're not in a situation where you go without hot water unless and until you can replace the anode.

On Monday, June 2, 2014 9:15:57 PM UTC-7, Jim Joyce wrote:
We recently bought a new house that has dual 50-gallon electric water
heaters. Each heater has a single 5500 Watt heating element.

snip

Just curious here. I have never heard of a WH with only one element and later you mention them being on 240 plugs.

Could you post the make and model, I'd like to look them up as one might work in my house.

Harry K

it might be more cost efficent to heavily insulate both water heaters. with electric water heaters it easy to add a water heater blanket

On Wed, 4 Jun 2014 16:42:16 +0200, nestork
wrote:


Jim:
It's actually a good idea to have two water heaters plumbed in series.

All that follows is true about in parallel too, right?

That way, if and when one water heater kicks the bucket, you can simply
switch over to the other water heater while the first one is being
replaced.

Also, you can use that second water heater while doing maintenance on
the first heater, like replacing the anode in it. That way you're not
in a situation where you go without hot water unless and until you can
replace the anode.

On Wed, 4 Jun 2014 09:07:20 -0700 (PDT), bob haller wrote:

it might be more cost efficent to heavily insulate both water heaters. with electric water heaters it easy to add a water heater blanket

The outer surfaces of the water heaters aren't noticeably warm, so I think
(lack of) insulation isn't an issue in this case. Thanks for the suggestion
though.

On Wed, 04 Jun 2014 17:39:25 -0400, micky wrote:

On Wed, 4 Jun 2014 16:42:16 +0200, nestork
wrote:


Jim:
It's actually a good idea to have two water heaters plumbed in series.

All that follows is true about in parallel too, right?

Based on what follows, I'm sure he meant to say parallel.


That way, if and when one water heater kicks the bucket, you can simply
switch over to the other water heater while the first one is being
replaced.

Also, you can use that second water heater while doing maintenance on
the first heater, like replacing the anode in it. That way you're not
in a situation where you go without hot water unless and until you can
replace the anode.

On Monday, June 9, 2014 1:57:58 AM UTC-4, Jim Joyce wrote:
On Wed, 4 Jun 2014 09:07:20 -0700 (PDT), bob haller wrote:



it might be more cost efficent to heavily insulate both water heaters. with electric water heaters it easy to add a water heater blanket



The outer surfaces of the water heaters aren't noticeably warm, so I think

(lack of) insulation isn't an issue in this case. Thanks for the suggestion

though.

The outside of a house isn't warm to the touch either, but insulation
is still important. How much difference adding insulation might make,
IDK, but I don't necessarily think the warm to the touch test means that
more insulation won't make a difference. And insulation for an
electric will be more effective because there is no flue up the middle
and you can put insulation on top too.

On Monday, June 9, 2014 9:39:18 AM UTC-4, trader_4 wrote:
On Monday, June 9, 2014 1:57:58 AM UTC-4, Jim Joyce wrote:

On Wed, 4 Jun 2014 09:07:20 -0700 (PDT), bob haller wrote:







it might be more cost efficent to heavily insulate both water heaters. with electric water heaters it easy to add a water heater blanket







The outer surfaces of the water heaters aren't noticeably warm, so I think



(lack of) insulation isn't an issue in this case. Thanks for the suggestion



though.



The outside of a house isn't warm to the touch either, but insulation

is still important. How much difference adding insulation might make,

IDK, but I don't necessarily think the warm to the touch test means that

more insulation won't make a difference. And insulation for an

electric will be more effective because there is no flue up the middle

and you can put insulation on top too.



plus as a example for a momentlets take this to a extreme....

how much electric would it take to keep the water hot in a vacuumn bottle.???

amost none. so insulation might help a lot, saving most of the energy you want to save by turning one water heater off, while still having the capacity

micky wrote:
On Wed, 4 Jun 2014 16:42:16 +0200, nestork
wrote:


Jim:
It's actually a good idea to have two water heaters plumbed in
series.
That way, if and when one water heater kicks the bucket, you can
simply switch over to the other water heater while the first one is
being replaced.

Also, you can use that second water heater while doing maintenance on
the first heater, like replacing the anode in it. That way you're
not in a situation where you go without hot water unless and until
you can replace the anode.


All that follows is true about in parallel too, right?



Actually, in series, it does not apply. In parallel, it does. If you turn off
the second of 2 heaters in series, the water in the second will get cold after
while of non-use, snd you will get cold water when you turn on the tap.

On Monday, June 9, 2014 9:52:44 AM UTC-4, bob haller wrote:
On Monday, June 9, 2014 9:39:18 AM UTC-4, trader_4 wrote:

On Monday, June 9, 2014 1:57:58 AM UTC-4, Jim Joyce wrote:



On Wed, 4 Jun 2014 09:07:20 -0700 (PDT), bob haller wrote:















it might be more cost efficent to heavily insulate both water heaters. with electric water heaters it easy to add a water heater blanket















The outer surfaces of the water heaters aren't noticeably warm, so I think







(lack of) insulation isn't an issue in this case. Thanks for the suggestion







though.







The outside of a house isn't warm to the touch either, but insulation



is still important. How much difference adding insulation might make,



IDK, but I don't necessarily think the warm to the touch test means that



more insulation won't make a difference. And insulation for an



electric will be more effective because there is no flue up the middle



and you can put insulation on top too.







plus as a example for a momentlets take this to a extreme....



how much electric would it take to keep the water hot in a vacuumn bottle.???



amost none. so insulation might help a lot, saving most of the energy you want to save by turning one water heater off, while still having the capacity

Another way of looking at it, compare it to an attic. In winter, the
attic could be 20F, while the heated air below is 70F. That's a 50F
temp delta and the sound science says having 12" of insulation makes a
substantial difference versus 4" of insulation. With a WH set at 130F,
sitting in a basement that's 55F, you have an 75F temp delta, 50% higher
than the attic example. That means you're going to have a roughly 50%
greater driving force to move heat out of the tank. IDK how much insulation
is in a WH, but I doubt it's even 4" thick. And IDK how much difference
it would actually make, but I woulnd't be surprised for it to have a
reasonable payback and for it to be worthwhile.

amost none. so insulation might help a lot, saving most of the energy you want to save by turning one water heater off, while still having the capacity



Another way of looking at it, compare it to an attic. In winter, the

attic could be 20F, while the heated air below is 70F. That's a 50F

temp delta and the sound science says having 12" of insulation makes a

substantial difference versus 4" of insulation. With a WH set at 130F,

sitting in a basement that's 55F, you have an 75F temp delta, 50% higher

than the attic example. That means you're going to have a roughly 50%

greater driving force to move heat out of the tank. IDK how much insulation

is in a WH, but I doubt it's even 4" thick. And IDK how much difference

it would actually make, but I woulnd't be surprised for it to have a

reasonable payback and for it to be worthwhile.

plus water heater insulation blankets are cheap.

On 6/10/2014 9:02 AM, trader_4 wrote:
On Monday, June 9, 2014 9:52:44 AM UTC-4, bob haller wrote:


how much electric would it take to keep the water hot in a vacuumn bottle.???



amost none. so insulation might help a lot, saving most of the energy you want to save by turning one water heater off, while still having the capacity

Another way of looking at it, compare it to an attic. In winter, the
attic could be 20F, while the heated air below is 70F. That's a 50F
temp delta and the sound science says having 12" of insulation makes a
substantial difference versus 4" of insulation. With a WH set at 130F,
sitting in a basement that's 55F, you have an 75F temp delta, 50% higher
than the attic example.


I'm thinking he should replace the 50 gallon water heater with a series
of vacuum bottles wrapped in 4" of insulation.

On Wed, 4 Jun 2014 07:49:35 -0700 (PDT), Harry K wrote:

On Monday, June 2, 2014 9:15:57 PM UTC-7, Jim Joyce wrote:
We recently bought a new house that has dual 50-gallon electric water
heaters. Each heater has a single 5500 Watt heating element.

snip

Just curious here. I have never heard of a WH with only one element and later you mention them being on 240 plugs.

Could you post the make and model, I'd like to look them up as one might work in my house.

Sorry for the delay. You've probably moved on by now, but for the record
these heaters are from:

State Industries
Model # ES652S0RT0W
240 VAC, Single Phase
Upper Watts: 0
Lower Watts: 5500
Total Watts: 5500
Capacity: 50 gallon


So now, 6 months after closing the inlet valve on one heater and unplugging
it from its receptacle, all has been well. We've had guests stay with us on
multiple occasions and there have been no issues with running out of hot
water. I would have to say that a single 50-gal heater seems to be perfectly
sufficient for our needs. I do plan to switch over to the disabled heater at
some point, possibly on a yearly basis.

On 12/1/2014 4:02 PM, Jim Joyce wrote:
[snip]
Sorry for the delay. You've probably moved on by now, but for the record
these heaters are from:

State Industries
Model # ES652S0RT0W
240 VAC, Single Phase
Upper Watts: 0
Lower Watts: 5500
Total Watts: 5500
Capacity: 50 gallon


So now, 6 months after closing the inlet valve on one heater and unplugging
it from its receptacle, all has been well. We've had guests stay with us on
multiple occasions and there have been no issues with running out of hot
water. I would have to say that a single 50-gal heater seems to be perfectly
sufficient for our needs. I do plan to switch over to the disabled heater at
some point, possibly on a yearly basis.


Are the heaters in parallel? Sounds like it if you can shut off the
inlet on either one and still have water flowing.

I'm thinking that if I were in your shoes and decided to keep both in
the system and yet only use one at any given time, I would plumb them in
series with a reversible bypass of some sort. Maybe I can clarify a bit
with a verbal diagram.

In position "1" Water heater "A" is turned off (electrically) and water
from the main (or water softener) flows into it (making it an old
fashioned tempering tank) and then flows on to Water heater "B" which is
active electrically and actually heats the water.

When you "switch over" annually or semi-annually, their functions are
are reversed and "B" becomes the tempering tank and "A" is the water heater.

With the arrangement that you are apparently using - a parallel setup
allowing for one heater to be completely shut down from both the
electrical system and the plumbing system, I'd be a bit concerned about
bacterial growth, etc. in the "off line" heater.

Does that make sense?

However you arrange valves to go down to one heater, I would definitely switch between them at least every six months, and probably drain the unused one as soon as it was off-line to get the sludge out of the bottom before it really congeals.

On Mon, 01 Dec 2014 22:16:49 -0600, Unquestionably Confused
wrote:

On 12/1/2014 4:02 PM, Jim Joyce wrote:
[snip]
Sorry for the delay. You've probably moved on by now, but for the record
these heaters are from:

State Industries
Model # ES652S0RT0W
240 VAC, Single Phase
Upper Watts: 0
Lower Watts: 5500
Total Watts: 5500
Capacity: 50 gallon


So now, 6 months after closing the inlet valve on one heater and unplugging
it from its receptacle, all has been well. We've had guests stay with us on
multiple occasions and there have been no issues with running out of hot
water. I would have to say that a single 50-gal heater seems to be perfectly
sufficient for our needs. I do plan to switch over to the disabled heater at
some point, possibly on a yearly basis.


Are the heaters in parallel? Sounds like it if you can shut off the
inlet on either one and still have water flowing.

Yes, they are in parallel.

I'm thinking that if I were in your shoes and decided to keep both in
the system and yet only use one at any given time, I would plumb them in
series with a reversible bypass of some sort. Maybe I can clarify a bit
with a verbal diagram.

In position "1" Water heater "A" is turned off (electrically) and water
from the main (or water softener) flows into it (making it an old
fashioned tempering tank) and then flows on to Water heater "B" which is
active electrically and actually heats the water.

When you "switch over" annually or semi-annually, their functions are
are reversed and "B" becomes the tempering tank and "A" is the water heater.

With the arrangement that you are apparently using - a parallel setup
allowing for one heater to be completely shut down from both the
electrical system and the plumbing system, I'd be a bit concerned about
bacterial growth, etc. in the "off line" heater.

I see what you're saying, but is bacterial growth a valid concern? The
doomsday prepper crowd has convinced me that bacterial growth isn't really
an issue when water is stored in the dark, as it would be here. I was
thinking a simple flush would be all I need to do when I switch over.

On Mon, 1 Dec 2014 20:39:09 -0800 (PST), "
wrote:

However you arrange valves to go down to one heater, I would definitely switch between them at least every six months, and probably drain the unused one as soon as it was off-line to get the sludge out of the bottom before it really congeals.


I can't drain the unused heater because its outlet pipe is connected to the
outlet pipe of the other heater. Each heater has a valve on its respective
inlet pipe, but no valve on the outlet pipes, so if I open the drain valve
on either heater, the other heater will simply (try to) reverse fill it
again.

Besides, "sludge" and "congeal" don't really describe the hard water
sediment, do they? Without actually having water flow through, and without
the heating cycle, I wasn't expecting new sediment to be an issue.

On Tuesday, December 2, 2014 1:56:35 AM UTC-5, Jim Joyce wrote:
On Mon, 1 Dec 2014 20:39:09 -0800 (PST), "
wrote:

However you arrange valves to go down to one heater, I would definitely switch between them at least every six months, and probably drain the unused one as soon as it was off-line to get the sludge out of the bottom before it really congeals.


I can't drain the unused heater because its outlet pipe is connected to the
outlet pipe of the other heater. Each heater has a valve on its respective
inlet pipe, but no valve on the outlet pipes, so if I open the drain valve
on either heater, the other heater will simply (try to) reverse fill it
again.


It would not refill, you could drain it, if you just shut off the incoming
cold water. But I agree, I'm not sure that I'd worry about draining it
because of worrying about bacteria growth. Especially if you're not using
the hot water for drinking, and/or as you suggested, flush it for awhile
when returning it to service.

I have some experience with a similar situation here. A friend has a house
with two tanks, gas, shut one down like you did, left it full of water.
Only negative was after not using it for a few years, went to put it back
in service before Hurricane Sandy. It would not fire. Upon inspection,
there was some rust debris visible that had fallen down into the pilot
light area. Probably just needed a vacuuming to solve that, but IDK for
sure what was later done to it. With electric, you don't have that issue.



Besides, "sludge" and "congeal" don't really describe the hard water
sediment, do they? Without actually having water flow through, and without
the heating cycle, I wasn't expecting new sediment to be an issue.

I agree.

On 12/2/2014 1:06 AM, wrote:
On Tue, 02 Dec 2014 00:53:52 -0600, Jim Joyce
wrote:

On Mon, 01 Dec 2014 22:16:49 -0600, Unquestionably Confused
wrote:

On 12/1/2014 4:02 PM, Jim Joyce wrote:
[snip]
Sorry for the delay. You've probably moved on by now, but for the record
these heaters are from:

State Industries
Model # ES652S0RT0W
240 VAC, Single Phase
Upper Watts: 0
Lower Watts: 5500
Total Watts: 5500
Capacity: 50 gallon


So now, 6 months after closing the inlet valve on one heater and unplugging
it from its receptacle, all has been well. We've had guests stay with us on
multiple occasions and there have been no issues with running out of hot
water. I would have to say that a single 50-gal heater seems to be perfectly
sufficient for our needs. I do plan to switch over to the disabled heater at
some point, possibly on a yearly basis.


Are the heaters in parallel? Sounds like it if you can shut off the
inlet on either one and still have water flowing.

Yes, they are in parallel.

They are interlocked by the top thermostat so they only come on one at
a time.
The top one starts the process by energizing the top element and when
the top thermostat is satisfied, it switches to the bottom element and
that thermostat.
If the bottom element went bad, the only indication would be you ran
out of hot water sooner than normal. If the top one goes bad, you
don't get any hot water because you never satisfy the top thermostat.

Read the OP's specs again. There is no upper element and, therefore,
there is no upper thermostat.

I am not sure your statement is entirely correct if the electric water
heater is dual element (as most are). Isn't the so-called "quick
recovery" mode/feature a function of both elements heating the water
simultaneously when demand is great?

On 12/2/2014 12:53 AM, Jim Joyce wrote:
On Mon, 01 Dec 2014 22:16:49 -0600, Unquestionably Confused
wrote:

On 12/1/2014 4:02 PM, Jim Joyce wrote:
[snip]
Sorry for the delay. You've probably moved on by now, but for the record
these heaters are from:

State Industries
Model # ES652S0RT0W
240 VAC, Single Phase
Upper Watts: 0
Lower Watts: 5500
Total Watts: 5500
Capacity: 50 gallon



[snip]

With the arrangement that you are apparently using - a parallel setup
allowing for one heater to be completely shut down from both the
electrical system and the plumbing system, I'd be a bit concerned about
bacterial growth, etc. in the "off line" heater.

I see what you're saying, but is bacterial growth a valid concern? The
doomsday prepper crowd has convinced me that bacterial growth isn't really
an issue when water is stored in the dark, as it would be here. I was
thinking a simple flush would be all I need to do when I switch over.

I honestly don't know if it would be a problem or not. I could ask my
daughter the biochemistry professor to get the answer for sureg BUT
we know that there's both aerobic and anaerobic bacteria and I'm not
sure that absence of light is going to mean much. Take a 8 oz bar if
Philly cream cheese, spit on it, place it in a sealed, black plastic
Tupperware container and put it in your t-shirt drawer for a month and
report back on your findings when you open it.g

Given that in my example of moving your system to a tempering tank
arrangement, I think that the question becomes moot. Same thing with
the sediment issue perhaps. Clearly it would obviate the need to flush
the water heater and lines when switching over.

On Tuesday, December 2, 2014 8:11:00 AM UTC-5, Unquestionably Confused wrote:
On 12/2/2014 1:06 AM, wrote:
On Tue, 02 Dec 2014 00:53:52 -0600, Jim Joyce
wrote:

On Mon, 01 Dec 2014 22:16:49 -0600, Unquestionably Confused
wrote:

On 12/1/2014 4:02 PM, Jim Joyce wrote:
[snip]
Sorry for the delay. You've probably moved on by now, but for the record
these heaters are from:

State Industries
Model # ES652S0RT0W
240 VAC, Single Phase
Upper Watts: 0
Lower Watts: 5500
Total Watts: 5500
Capacity: 50 gallon


So now, 6 months after closing the inlet valve on one heater and unplugging
it from its receptacle, all has been well. We've had guests stay with us on
multiple occasions and there have been no issues with running out of hot
water. I would have to say that a single 50-gal heater seems to be perfectly
sufficient for our needs. I do plan to switch over to the disabled heater at
some point, possibly on a yearly basis.


Are the heaters in parallel? Sounds like it if you can shut off the
inlet on either one and still have water flowing.

Yes, they are in parallel.

They are interlocked by the top thermostat so they only come on one at
a time.
The top one starts the process by energizing the top element and when
the top thermostat is satisfied, it switches to the bottom element and
that thermostat.
If the bottom element went bad, the only indication would be you ran
out of hot water sooner than normal. If the top one goes bad, you
don't get any hot water because you never satisfy the top thermostat.

Read the OP's specs again. There is no upper element and, therefore,
there is no upper thermostat.

I am not sure your statement is entirely correct if the electric water
heater is dual element (as most are). Isn't the so-called "quick
recovery" mode/feature a function of both elements heating the water
simultaneously when demand is great?

I don't think both are on at the same time with the typical residential WH.
The ones I've seen, work as gfre described. They are rated at say 4500W
and have two elements that size. Only one comes on at a time. That reduces
the circuit ampacity required. As temp goes down, the bottom comes on
first. If the upper level water gets cool enough, then it switches the
bottom off and the top on, to provide more heating to the water that is
going to be drawn first.

Why the OP's WH only has a bottom element, IDK. That isn't typical and
seems dumb.

On 12/2/2014 8:05 AM, trader_4 wrote:
On Tuesday, December 2, 2014 8:11:00 AM UTC-5, Unquestionably Confused wrote:
On 12/2/2014 1:06 AM, wrote:

[snip]


I am not sure your statement is entirely correct if the electric water
heater is dual element (as most are). Isn't the so-called "quick
recovery" mode/feature a function of both elements heating the water
simultaneously when demand is great?

I don't think both are on at the same time with the typical residential WH.
The ones I've seen, work as gfre described. They are rated at say 4500W
and have two elements that size. Only one comes on at a time. That reduces
the circuit ampacity required. As temp goes down, the bottom comes on
first. If the upper level water gets cool enough, then it switches the
bottom off and the top on, to provide more heating to the water that is
going to be drawn first.

Looks as if you're correct from the limited "research" Google and I just
didg The upper element is "responsible" for heating about 1/4 of the
tank's capacity and provides the quick recovery


Why the OP's WH only has a bottom element, IDK. That isn't typical and
seems dumb.

Agreed, single element would make sense in a small, point of use heater
(like in a workshop restroom, etc) but with 50 gallons, I sure wouldn't
want one.

On Tue, 02 Dec 2014 08:21:50 -0600, Unquestionably Confused
wrote:

On 12/2/2014 8:05 AM, trader_4 wrote:

Why the OP's WH only has a bottom element, IDK. That isn't typical and
seems dumb.

Agreed, single element would make sense in a small, point of use heater
(like in a workshop restroom, etc) but with 50 gallons, I sure wouldn't
want one.

It's not as if I selected it myself. g The home builder decided that twin
50-gal heaters would be nice, and he apparently selected this model that has
a single element. Perhaps he bought in quantity and got a deal.

If I really had to, I could make this a 5 bedroom house, meaning there could
potentially be what, about 10 people living here in 3000 square feet,
sharing 3 bathrooms? Fully populated like that, maybe dual 50-gal heaters
make sense, but there are only two of us here, not counting occasional
guests, so a total of 100 gallons of hot water seems excessive.

On Tue, 2 Dec 2014 03:46:21 -0800 (PST), trader_4
wrote:

On Tuesday, December 2, 2014 1:56:35 AM UTC-5, Jim Joyce wrote:

I can't drain the unused heater because its outlet pipe is connected to the
outlet pipe of the other heater. Each heater has a valve on its respective
inlet pipe, but no valve on the outlet pipes, so if I open the drain valve
on either heater, the other heater will simply (try to) reverse fill it
again.


It would not refill, you could drain it, if you just shut off the incoming
cold water. But I agree, I'm not sure that I'd worry about draining it
because of worrying about bacteria growth. Especially if you're not using
the hot water for drinking, and/or as you suggested, flush it for awhile
when returning it to service.

I agree with everything you said, except that it would really try to refill
from the other heater. The only way to drain one and keep it drained is to
shut off the water to both heater units.

On Tuesday, December 2, 2014 12:53:01 PM UTC-5, Jim Joyce wrote:
On Tue, 2 Dec 2014 03:46:21 -0800 (PST), trader_4
wrote:

On Tuesday, December 2, 2014 1:56:35 AM UTC-5, Jim Joyce wrote:

I can't drain the unused heater because its outlet pipe is connected to the
outlet pipe of the other heater. Each heater has a valve on its respective
inlet pipe, but no valve on the outlet pipes, so if I open the drain valve
on either heater, the other heater will simply (try to) reverse fill it
again.


It would not refill, you could drain it, if you just shut off the incoming
cold water. But I agree, I'm not sure that I'd worry about draining it
because of worrying about bacteria growth. Especially if you're not using
the hot water for drinking, and/or as you suggested, flush it for awhile
when returning it to service.

I agree with everything you said, except that it would really try to refill
from the other heater. The only way to drain one and keep it drained is to
shut off the water to both heater units.

yes, this is correct. And definitely cut the power to the one valved off otherwise it'll build pressure and pop the T/P valve when it goes into a heating cycle.

I'm really not sure whether it's better to drain or leave full, from a corrosion standpoint. I'd be worried about anaerobic bacteria possibly growing in a stagnant full WH as well.

nate