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Default Most efficient water heater?

On Tue, 18 Mar 2008 07:30:39 -0700 (PDT), ransley wrote:
Where's the A.O. Smith Vertex model GPHE-50 that Bubba recommended?

Don www.donwiss.com (e-mail link at home page bottom).


I saw one unit near the bottom with an Energy Factor of 70, only a few
in the 60s and most in the 50-60 range.


I should have mentioned that I searched for that PDF during my GAS water
heater replacement. http://tinyurl.com/38eh4d

That PDF only contained residential GAS water heater specifications (very
many hundreds or even a thousand or more).

It did not have any residential ELECTRIC water heater efficiency ratings
(some of which approach 98% due to the fact no heat goes up the flue; it's
all absorbed by the water).

Donna
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On Mar 19, 11:51*pm, Donna Ohl wrote:
On Wed, 19 Mar 2008 04:32:02 -0700 (PDT), ransley wrote:
98% water heaters are common even 96% boilers


I think the reason for this is somewhat misleading.

If I understand this correctly, almost all the heat energy put into an
electric heater gets put into the water. Basically, the water cools the
heater coils down by taking the heat off the heater coil.

In the case of a gas water heater, the water cools down the flame by taking
heat off the flame (figuratively speaking) but a LOT of heat goes up the
flue.

They baffle the flue to slow down the rising air but they have to let the
hot air out. If they cooled the hot air to room temperature, it wouldn't
rise and get out of the house and that would be a bad thing from the
standpoint of carbon monoxide poisoning.

So, I think the fact that all none of the heat energy that went into the
electric coils goes up any flue - it's all absorbed by the water - is what
makes the electric water heater 98% efficiency.

But, as someone stated, I suspect the power generation is about 70%
efficiency, so, the true efficiency of electric water heating must be
vastly lower than 98% taking distribution into account.

But, how can we account for that true efficiency?

Donna


Electric are all 100% efficent, all energy consumed is used to heat
water, and energy factor should be near 100 as well with great
insulation. Almost all gas water heaters burners are about 80-83%
efficent, but an additional 17-20% goes up the chimney 24 hrs a day,
Energy Factor ratings account for loss up the center uninsulated flue
part of the tank and reflect overall efficency, which for most gas
tank is 50-60 with one I saw of 70. Condensing gas water heaters,
Boilers, furnaces, are different, have a second exchanger that lowers
flue temp to near room temp and are forced out the flue by a fan. A
condensing 93% water heater wont loose 20% in flue loss since the fan
stopped some of the heat loss, but even the best condensing tank water
heater of 93% may only be 83% Energy Factor [I guess]. Condensing tank
water heaters are really commercial units costing thousands. AO Smith
has them, I own one a 175000 btu unit, a Cyclone. For most, electrics
are and always will be more expensive to run unless you have a cheaper
Hydro Dam nearby, since for most oil- gas products generate
electricity. Someone stated 70% for electric, that is not true to you
for what you consume and pay, he was talking about transmission line
loss, for you electric tank is 100% efficient, but here electricity is
still 30% more than NG. If nobody in your neighboorhood has an
electric furnace then you can bet Ng is still cheaper per Btu. Now in
the last 6 months all petroleum products are going up fast, but
electric will follow in the long run.
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wrote:
On Tue, 18 Mar 2008 23:45:30 -0500, Don Ocean
wrote:

ransley wrote:
On Mar 18, 4:46 am, Don Wiss wrote:
On Mon, 17 Mar 2008, Donna Ohl wrote:
I challenge you to find a water heater efficiency rating NOT in this
36-page listing for a water heater currently sold in the USA.
http://tinyurl.com/38eh4d
(long url)
http://www.gamanet.org/gama/inforeso...ntLaunch/C2AAF...
Where's the A.O. Smith Vertex model GPHE-50 that Bubba recommended?

Don www.donwiss.com (e-mail link at home page bottom).
I saw one unit near the bottom with an Energy Factor of 70, only a few
in the 60s and most in the 50-60 range. Vertex, I have a several year
old similar AO condensing ccommercial unit but I only know its 92%
efficent or so

I am aware of no water heater approaching 92% efficiency. Way too many
losses to achieve that.. Even Boiler technology can't do that yet


I have one.

It's electric :-)


I differ to your electrifying disclosure. ;-p




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Bubba wrote:
On Tue, 18 Mar 2008 23:45:30 -0500, Don Ocean
wrote:

ransley wrote:
On Mar 18, 4:46 am, Don Wiss wrote:
On Mon, 17 Mar 2008, Donna Ohl wrote:
I challenge you to find a water heater efficiency rating NOT in this
36-page listing for a water heater currently sold in the USA.
http://tinyurl.com/38eh4d
(long url)
http://www.gamanet.org/gama/inforeso...ntLaunch/C2AAF...
Where's the A.O. Smith Vertex model GPHE-50 that Bubba recommended?

Don www.donwiss.com (e-mail link at home page bottom).
I saw one unit near the bottom with an Energy Factor of 70, only a few
in the 60s and most in the 50-60 range. Vertex, I have a several year
old similar AO condensing ccommercial unit but I only know its 92%
efficent or so

I am aware of no water heater approaching 92% efficiency. Way too many
losses to achieve that.. Even Boiler technology can't do that yet


AO Smith has the Vertex water heater that gets 90%
Weil-McLain has a boiler that does 98% at low temp
Bubba


Both have been proven to be fairy tales. It is all in how its measured.
I have a number of AO Smiths Mexican Vortex's out there and a number of
the same type by Rheem.. Both about the same and the damned electronics
eats the whole card when it goes. It gets even worse when you add the
electric consumption to run the ignito0r and controls. Low temperature
on the Weil-Mclain is almost 100 percent when the thermostat is off. ;-p

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ransley wrote:
On Mar 18, 11:45 pm, Don Ocean wrote:
ransley wrote:
On Mar 18, 4:46 am, Don Wiss wrote:
On Mon, 17 Mar 2008, Donna Ohl wrote:
I challenge you to find a water heater efficiency rating NOT in this
36-page listing for a water heater currently sold in the USA.
http://tinyurl.com/38eh4d
(long url)
http://www.gamanet.org/gama/inforeso...ntLaunch/C2AAF...
Where's the A.O. Smith Vertex model GPHE-50 that Bubba recommended?
Don www.donwiss.com (e-mail link at home page bottom).
I saw one unit near the bottom with an Energy Factor of 70, only a few
in the 60s and most in the 50-60 range. Vertex, I have a several year
old similar AO condensing ccommercial unit but I only know its 92%
efficent or so

I am aware of no water heater approaching 92% efficiency. Way too many
losses to achieve that.. Even Boiler technology can't do that yet

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- Show quoted text -


92-93-94 even 98% water heaters are common even 96% boilers, even a
94% tankless. AO Smith Cyclone tank, Takagi tankless and a Canadian
firm makes a 98% commercial hw boiler, 5 years ago I installed at my
apt a 92% 1900000 btu AO Smith Cyclone. these are all condensing
units,


Nope.. ;-p

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wrote:
On Mar 19, 4:15�pm, ransley wrote:
On Mar 19, 1:19�pm, " wrote:

my tankless add on was only for use when familiy is visiting, the
remainder of the time my 50 gallon high btu tank is fine.
now 7 people pile in here, and it can become a problem espically when
incoming water temperature is 40 degrees

Its alot of money to put in a tankless and not get the savings year
around, first you need to get the supply tested with all other gas
apliances running to be sure no upgrade is neded. Do 2 people shower
now at the same time, I dont think you will benefit having a tankless
before a tank and it will actualy cost more to run since both units
burners are probably near in efficency, I put my tankless after my
tank with bypass valves incase my old tank leaks, but i havnt used it
since installing the tankless, the cheap Bosch.


its more of a idle thought, the minor standby losses of a regular tank
dont bother me, and our tank is plenty big enough, except when family
visits. with washing clothes, doing laundry and showering its a busy
hot water using place. and our showers have the flow restrictors
removed.....

but a new kitchen dining room gut job is a lot more likely and
probably better of use of money kinda nervous the economy may hurt
our income and gasoline is killing my service business


Thank your lucky stars you don't own a long haul trucking business.
Price diesel for a rude awakening.

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"Donna Ohl" wrote in message
. net...
On Wed, 19 Mar 2008 04:32:02 -0700 (PDT), ransley wrote:
So, I think the fact that all none of the heat energy that went into the
electric coils goes up any flue - it's all absorbed by the water - is what
makes the electric water heater 98% efficiency.


Correct.

But, as someone stated, I suspect the power generation is about 70%
efficiency,

so, the true efficiency of electric water heating must be
vastly lower than 98% taking distribution into account.

But, how can we account for that true efficiency?

Donna


Average power generation isn't anything like 70% efficient. Typical
efficiency for a coal fired station is 30-40% with only the latest
generation achieving 60%+. Gas fired around 47% and nuclear around 38%. Then
another 5-6% is lost in transmission. The average depends on what mix your
country has but I can't see it being much above 40-50% overall by the time
it reaches your house.

This web site compares the cost of different fuel sources in the UK. It's
the only site I've seen that takes into account boiler efficiency. The key
figure is the middle one "Pence per kWh after boiler efficiency". The actual
boiler efficiency is in brackets...

http://www.nottenergy.com/energy-costs-comparison2

Note that electric heating is indeed 100% efficient but the cost of that
electricity makes it expensive to run.

Heat Pumps have efficiencies of over 100% and in the case of a ground source
heat pump (GSHP) around 350%. This more than compensates for the loss of
efficiency producing the electricity needed to power. Overall a GSHP is the
cheapest system to run (ignoring capital costs). It would be interesting to
know if anyone makes a small scale gas or oil powered GSHP and how the
efficiency of those compare.

In theory it would _just_ be possible to use the heat from a GSHP to power a
Stirling engine to power the GSHP. This would not violate COE because there
is a heat source (the sun) providing power into the system. However most of
the heat produced by the GSHP would go into the stirling engine with very
little left over to heat your house. Stirling engines that big would also be
rather big physically. Overall such a system would be too big and expensive
to be practical - but it would be free to run.


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"CWatters" wrote in message
...

"Donna Ohl" wrote in message
. net...
On Wed, 19 Mar 2008 04:32:02 -0700 (PDT), ransley wrote:
So, I think the fact that all none of the heat energy that went into the
electric coils goes up any flue - it's all absorbed by the water - is

what
makes the electric water heater 98% efficiency.


Correct.


Actually it's 100% efficient. I mean your reasoning is correct.


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Default Most efficient water heater?

you can get too would up over efficency ratings, nothing is 100% even
electric loses a little to the room.

and one must be aware that cost to buy can exceed savings on whatever
your trying to be more efficent with



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wrote
you can get too would up over efficency ratings, nothing is 100%


Basically what we're talking about with the efficiency of water heaters is
the percentage of the energy that's put into the system that actually gets
applied to the task of heating water. And, of course, a lot depends on where
you define the boundary of the system.


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"CWatters" wrote in message
...

"CWatters" wrote in message
...

"Donna Ohl" wrote in message
. net...
On Wed, 19 Mar 2008 04:32:02 -0700 (PDT), ransley wrote:
So, I think the fact that all none of the heat energy that went into

the
electric coils goes up any flue - it's all absorbed by the water - is

what
makes the electric water heater 98% efficiency.


Correct.


Actually it's 100% efficient. I mean your reasoning is correct.



wrote in message
...
you can get too would up over efficency ratings, nothing is 100% even
electric loses a little to the room.


Yes I knew I was wrong the moment I posted it. I was thinking of electric
heating and forgot that when heating water some heat would be lost to the
room.


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On Sun, 16 Mar 2008 20:27:22 -0400, Don Wiss wrote:
I get confused with all the models. Efficiency information is hidden.


A GUI is available to look up the efficiency of any water heater,
residential or commercial at http://www.gamapower.org

For example, residential hot water heater efficiency can be obtained at
http://www.gamapower.org/water.php

Or, just call GAMA at 908-464-8200

Donna
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On Mon, 24 Mar 2008, Donna Ohl wrote:

On Sun, 16 Mar 2008 20:27:22 -0400, Don Wiss wrote:
I get confused with all the models. Efficiency information is hidden.


A GUI is available to look up the efficiency of any water heater,
residential or commercial at http://www.gamapower.org

For example, residential hot water heater efficiency can be obtained at
http://www.gamapower.org/water.php


What a poorly designed page! I gave up. Most annoying is each time you
return to the page to make a change it clears all your input away and you
have to reinput everything.

And it does not seem to include the model GPHE-50 (AO Smith Vertex) that I
just had installed.

Don www.donwiss.com (e-mail link at home page bottom).
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Do you not believe the manufacturer that it's 90% efficient? Are you trying
to verify their claims or what?
http://www.ho****er.com/lit/spec/res...RG-SS01306.pdf



"Don Wiss" wrote in message
...
On Mon, 24 Mar 2008, Donna Ohl wrote:

On Sun, 16 Mar 2008 20:27:22 -0400, Don Wiss wrote:
I get confused with all the models. Efficiency information is hidden.


A GUI is available to look up the efficiency of any water heater,
residential or commercial at http://www.gamapower.org

For example, residential hot water heater efficiency can be obtained at
http://www.gamapower.org/water.php


What a poorly designed page! I gave up. Most annoying is each time you
return to the page to make a change it clears all your input away and you
have to reinput everything.

And it does not seem to include the model GPHE-50 (AO Smith Vertex) that I
just had installed.

Don www.donwiss.com (e-mail link at home page bottom).





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A GUI is available to look up the efficiency of any water heater,
residential or commercial at http://www.gamapower.org

For example, residential hot water heater efficiency can be obtained at
http://www.gamapower.org/water.php


What a poorly designed page! I gave up. Most annoying is each time you
return to the page to make a change it clears all your input away and you
have to reinput everything.

And it does not seem to include the model GPHE-50 (AO Smith Vertex) that I
just had installed.

Go to link - PDF file - pg. 15 (document page 217) 4th entry down for A.O.
Smith
http://www.gamanet.org/gama/inforesources.nsf/vAttachmentLaunch/BD9C57BA8477D8E185256E9000606CD0/$FILE/12-07-gas-cwh.pdf

Also:
http://www.saskenergy.com/saving_ene...terHeaters.pdf


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"Bubba" wrote in message
...
On Sun, 23 Mar 2008 23:01:07 -0400, Don Wiss
wrote:

On Mon, 24 Mar 2008, Donna Ohl wrote:

On Sun, 16 Mar 2008 20:27:22 -0400, Don Wiss wrote:
I get confused with all the models. Efficiency information is hidden.

A GUI is available to look up the efficiency of any water heater,
residential or commercial at http://www.gamapower.org

For example, residential hot water heater efficiency can be obtained at
http://www.gamapower.org/water.php


What a poorly designed page! I gave up. Most annoying is each time you
return to the page to make a change it clears all your input away and you
have to reinput everything.

And it does not seem to include the model GPHE-50 (AO Smith Vertex) that I
just had installed.

Don www.donwiss.com (e-mail link at home page bottom).


Are you sure maybe you just arent searching correctly?
When you do a "Run Query" and it comes back with no results
DONT hit the back button on your browser.
Use the "Modify Query" on the page. It rolls back and there is all
your past info you typed.
Bubba


But....but.... but.... thats just too easy!! it makes too much sense!!

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On Mar 16, 8:27 pm, Don Wiss wrote:
I'd like to switch to a direct vent water heater. Looking at the A.O. Smith
site I get confused with all the models. Efficiency information is hidden.
There is no convenient chart to distinguish the models. It would seem that
these are my choice:

ProMax Closed Combustion Power Direct-Vent
ProMax Power Vent (C3 FVIR)
Power House Sealed Shot Power Direct-Vent
Power House Power Shot Power-Vent

But I can't figure out what is different. Plus each of the above has
variants.

So, what is the most efficient 50 gallon tank water heater with the longest
tank warranty? The run would be about 40 feet and will have a bunch of 90
degree bends.

Don www.donwiss.com (e-mail link at home page bottom)


Take a look at Voyager water heaters similar to the AO Smith Cyclone.
They (Voyager) have stainless heat exchangers. It's the recovery rate
and efficiencies that you want to pay attention too.
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