Any ideas as to why my son's electric hot water heater electrode burned
open? It was cathastrophic! The electrode was replaced and all is OK.

Al

I would venture to say that the inside wall of the tank has galvanic
corrosion and will fail shortly.

Most folks don't bother to drain off a few gallons of water from the faucet
on the bottom of the heater much less replace the Zinc anodes.
Draining off the water removes sediment that forms from heating water that
contains dissolved minerals. Minerals precipitate out and eventually coat
over the heating elements. This causes a hot spot that accelerates failure.
There are usually two heaters in the tank. the one that failed is the lower
one?

Zinc anodes should be replaced or checked at 5 years or so. They are
generally accessed by screwing out a plug on the top of the tank. I heard
that some are attached to (can't remember) the water inlet or outlet pipe.
Got to disconnect the plumbing and screw out the fitting.


"Al" wrote in message
...
Any ideas as to why my son's electric hot water heater electrode burned
open? It was cathastrophic! The electrode was replaced and all is OK.

Al

In article K79Qi.1215$pl2.654@trndny09, "oppie"
wrote:

I would venture to say that the inside wall of the tank has galvanic
corrosion and will fail shortly.

Most folks don't bother to drain off a few gallons of water from the faucet
on the bottom of the heater much less replace the Zinc anodes.
Draining off the water removes sediment that forms from heating water that
contains dissolved minerals. Minerals precipitate out and eventually coat
over the heating elements. This causes a hot spot that accelerates failure.
There are usually two heaters in the tank. the one that failed is the lower
one?

Zinc anodes should be replaced or checked at 5 years or so. They are
generally accessed by screwing out a plug on the top of the tank. I heard
that some are attached to (can't remember) the water inlet or outlet pipe.
Got to disconnect the plumbing and screw out the fitting.


"Al" wrote in message
...
Any ideas as to why my son's electric hot water heater electrode burned
open? It was cathastrophic! The electrode was replaced and all is OK.

Al




Sorry, but I forgot to mention that the unit is just over a year old. I
do admit it must be a cheap unit. However, my son, whose unit it was,
said that there have been no other failures in his condo of 35 units.
All of which are less than 2 years old.

Al

"Lynn Richardson" wrote in message
...
On Sat, 13 Oct 2007 19:22:27 GMT, Al wrote:

Any ideas as to why my son's electric hot water heater electrode burned
open? It was cathastrophic! The electrode was replaced and all is OK.

Al

The main parameter that controls electric heater element lifetime is power
vs
surface area and mineral accretion depth. As the mineral depth increases
(adding to the thermal resitance to the water) the heater wire temp goes
up,
eventually to the point it either breaks (potentially creating a
disastrous
temporary electric arc) or melts the insulating tube it runs through
allowing
water to hit the hot wire, making for a nice steam explosion in the tube.

Cheapy water heaters use the smallest element size possible to reduce
costs.
This makes the temperature gradient from the wire to the water higher than
a
larger elements.

When replacing it, pick the largest physical element size available for
the same
wattage/voltage rating. This will give a much longer lifetime since the
heater
wire runs at a lower temperature.

I'll agree with that.
If in doubt, go to a plumbing supply store rather than one of the big boxes
for the replacement heater. You'll pay a bit more but they will generally
give you good advice.

Sorry, but I forgot to mention that the unit is just over a year old. I
do admit it must be a cheap unit. However, my son, whose unit it was,
said that there have been no other failures in his condo of 35 units.
All of which are less than 2 years old.

Al

They should last years and years.... Maybe a shoddy builder/plumber fitted a
second hand one in your case?

On Mon, 15 Oct 2007 10:35:33 GMT, "TT_Man"
wrote:


Sorry, but I forgot to mention that the unit is just over a year old. I
do admit it must be a cheap unit. However, my son, whose unit it was,
said that there have been no other failures in his condo of 35 units.
All of which are less than 2 years old.

Al

They should last years and years.... Maybe a shoddy builder/plumber fitted a
second hand one in your case?


Oh, always looking for evil in this world... g

I'd guess when they built the tank, the assembly line worker
accidently nicked the element inserting it into the hole. This does
happen (maybe too often?) and damages the anti-corrosion coating on
the element letting it fail too soon.

Another possibility (more remote) is some contamination in the
incoming water.

A third possibility si that the installer accidently powered it up
before it was full of water, overheating and damaging the element but
not destroying it (he was slightly lucky).

I'll agree: they should last for at least four years if the water is
acidic, and longer if it is PH neutral.

Al wrote:

Any ideas as to why my son's electric hot water heater electrode burned
open? It was cathastrophic! The electrode was replaced and all is OK.

Al

[Image]

The way that the entire element is curved makes me think that it was
severely overheated (probably run dry) at some time.

If the insulation were to fail at one point on an otherwise intact
element, the damage would probably be localized to that one spot.

--
Paul Hovnanian
-----------------------------------------------------------------------
Procrastinators: The leaders for tomorrow.

In article ,
"Paul Hovnanian P.E." wrote:

Al wrote:

Any ideas as to why my son's electric hot water heater electrode burned
open? It was cathastrophic! The electrode was replaced and all is OK.

Al

[Image]

The way that the entire element is curved makes me think that it was
severely overheated (probably run dry) at some time.

If the insulation were to fail at one point on an otherwise intact
element, the damage would probably be localized to that one spot.

I think you're right. As far as I know, it was the only one to fail in
that condo complex so early, but still after the warranty expired. Grrr!

Al

Al wrote:
In article ,
"Paul Hovnanian P.E." wrote:

Al wrote:
Any ideas as to why my son's electric hot water heater electrode burned
open? It was cathastrophic! The electrode was replaced and all is OK.

Al

[Image]
The way that the entire element is curved makes me think that it was
severely overheated (probably run dry) at some time.

If the insulation were to fail at one point on an otherwise intact
element, the damage would probably be localized to that one spot.

I think you're right. As far as I know, it was the only one to fail in
that condo complex so early, but still after the warranty expired. Grrr!


There should have been a thermo-switch preventing overheating. Should
have ... maybe pick a better brand next time you need one. Heck, even
our little hot water dispenser has that secondary protection. Ok, that
one is non-resettable but still $1.50 for a thermo-fuse sure beats $150
for a heater.

--
Regards, Joerg

http://www.analogconsultants.com/

Joerg wrote:

Al wrote:
In article ,
"Paul Hovnanian P.E." wrote:

Al wrote:
Any ideas as to why my son's electric hot water heater electrode burned
open? It was cathastrophic! The electrode was replaced and all is OK.

Al

[Image]
The way that the entire element is curved makes me think that it was
severely overheated (probably run dry) at some time.

If the insulation were to fail at one point on an otherwise intact
element, the damage would probably be localized to that one spot.

I think you're right. As far as I know, it was the only one to fail in
that condo complex so early, but still after the warranty expired. Grrr!


There should have been a thermo-switch preventing overheating. Should
have ... maybe pick a better brand next time you need one. Heck, even
our little hot water dispenser has that secondary protection. Ok, that
one is non-resettable but still $1.50 for a thermo-fuse sure beats $150
for a heater.

Problem: The overtemp thermo switches are mounted on the tank near the
element. They will react to an overtemp condition with a full tank
properly. But the element hanging in air will need to reach a very high
temperature in order to conduct enough heat along its length to the tank
in order to trip the safety switch.

--
Paul Hovnanian
------------------------------------------------------------------
When cryptography is outlawed, bayl bhgynjf jvyy unir cevinpl.
-- Etaoin Shrdlu

Paul Hovnanian P.E. wrote:
Joerg wrote:
Al wrote:
In article ,
"Paul Hovnanian P.E." wrote:

Al wrote:
Any ideas as to why my son's electric hot water heater electrode burned
open? It was cathastrophic! The electrode was replaced and all is OK.

Al

[Image]
The way that the entire element is curved makes me think that it was
severely overheated (probably run dry) at some time.

If the insulation were to fail at one point on an otherwise intact
element, the damage would probably be localized to that one spot.
I think you're right. As far as I know, it was the only one to fail in
that condo complex so early, but still after the warranty expired. Grrr!

There should have been a thermo-switch preventing overheating. Should
have ... maybe pick a better brand next time you need one. Heck, even
our little hot water dispenser has that secondary protection. Ok, that
one is non-resettable but still $1.50 for a thermo-fuse sure beats $150
for a heater.

Problem: The overtemp thermo switches are mounted on the tank near the
element. They will react to an overtemp condition with a full tank
properly. But the element hanging in air will need to reach a very high
temperature in order to conduct enough heat along its length to the tank
in order to trip the safety switch.


On ours it was mounted right at the root of the element. That location
would get hot really fast if there wasn't any water.

--
Regards, Joerg

http://www.analogconsultants.com/

In article ,
Joerg wrote:

Al wrote:
In article ,
"Paul Hovnanian P.E." wrote:

Al wrote:
Any ideas as to why my son's electric hot water heater electrode burned
open? It was cathastrophic! The electrode was replaced and all is OK.

Al

[Image]
The way that the entire element is curved makes me think that it was
severely overheated (probably run dry) at some time.

If the insulation were to fail at one point on an otherwise intact
element, the damage would probably be localized to that one spot.

I think you're right. As far as I know, it was the only one to fail in
that condo complex so early, but still after the warranty expired. Grrr!


There should have been a thermo-switch preventing overheating. Should
have ... maybe pick a better brand next time you need one. Heck, even
our little hot water dispenser has that secondary protection. Ok, that
one is non-resettable but still $1.50 for a thermo-fuse sure beats $150
for a heater.

Nothing to pick. It came with the condo.

Al

Joerg wrote:

Paul Hovnanian P.E. wrote:
Joerg wrote:
Al wrote:
In article ,
"Paul Hovnanian P.E." wrote:

Al wrote:
Any ideas as to why my son's electric hot water heater electrode burned
open? It was cathastrophic! The electrode was replaced and all is OK.

Al

[Image]
The way that the entire element is curved makes me think that it was
severely overheated (probably run dry) at some time.

If the insulation were to fail at one point on an otherwise intact
element, the damage would probably be localized to that one spot.
I think you're right. As far as I know, it was the only one to fail in
that condo complex so early, but still after the warranty expired. Grrr!

There should have been a thermo-switch preventing overheating. Should
have ... maybe pick a better brand next time you need one. Heck, even
our little hot water dispenser has that secondary protection. Ok, that
one is non-resettable but still $1.50 for a thermo-fuse sure beats $150
for a heater.

Problem: The overtemp thermo switches are mounted on the tank near the
element. They will react to an overtemp condition with a full tank
properly. But the element hanging in air will need to reach a very high
temperature in order to conduct enough heat along its length to the tank
in order to trip the safety switch.


On ours it was mounted right at the root of the element. That location
would get hot really fast if there wasn't any water.

That's a better design than ours. So how did we come to be the sole
remaining superpower in the world with such crappy engineering?

--
Paul Hovnanian
------------------------------------------------------------------
professor; n, One who talks in someone else's sleep.

In article ,
"Paul Hovnanian P.E." wrote:

Joerg wrote:

Paul Hovnanian P.E. wrote:
Joerg wrote:
Al wrote:
In article ,
"Paul Hovnanian P.E." wrote:

Al wrote:
Any ideas as to why my son's electric hot water heater electrode
burned
open? It was cathastrophic! The electrode was replaced and all is OK.

Al

[Image]
The way that the entire element is curved makes me think that it was
severely overheated (probably run dry) at some time.

If the insulation were to fail at one point on an otherwise intact
element, the damage would probably be localized to that one spot.
I think you're right. As far as I know, it was the only one to fail in
that condo complex so early, but still after the warranty expired.
Grrr!

There should have been a thermo-switch preventing overheating. Should
have ... maybe pick a better brand next time you need one. Heck, even
our little hot water dispenser has that secondary protection. Ok, that
one is non-resettable but still $1.50 for a thermo-fuse sure beats $150
for a heater.

Problem: The overtemp thermo switches are mounted on the tank near the
element. They will react to an overtemp condition with a full tank
properly. But the element hanging in air will need to reach a very high
temperature in order to conduct enough heat along its length to the tank
in order to trip the safety switch.


On ours it was mounted right at the root of the element. That location
would get hot really fast if there wasn't any water.

That's a better design than ours. So how did we come to be the sole
remaining superpower in the world with such crappy engineering?


Yeah, and we've been building cars for over a hundred years and they
still have failures and poor ergonomics. And they are designed all over
the world crappily. (Is that a word?)

Al

Paul Hovnanian P.E. wrote:
Joerg wrote:
Paul Hovnanian P.E. wrote:
Joerg wrote:
Al wrote:
In article ,
"Paul Hovnanian P.E." wrote:

Al wrote:
Any ideas as to why my son's electric hot water heater electrode burned
open? It was cathastrophic! The electrode was replaced and all is OK.

Al

[Image]
The way that the entire element is curved makes me think that it was
severely overheated (probably run dry) at some time.

If the insulation were to fail at one point on an otherwise intact
element, the damage would probably be localized to that one spot.
I think you're right. As far as I know, it was the only one to fail in
that condo complex so early, but still after the warranty expired. Grrr!

There should have been a thermo-switch preventing overheating. Should
have ... maybe pick a better brand next time you need one. Heck, even
our little hot water dispenser has that secondary protection. Ok, that
one is non-resettable but still $1.50 for a thermo-fuse sure beats $150
for a heater.
Problem: The overtemp thermo switches are mounted on the tank near the
element. They will react to an overtemp condition with a full tank
properly. But the element hanging in air will need to reach a very high
temperature in order to conduct enough heat along its length to the tank
in order to trip the safety switch.

On ours it was mounted right at the root of the element. That location
would get hot really fast if there wasn't any water.

That's a better design than ours. So how did we come to be the sole
remaining superpower in the world with such crappy engineering?


I guess because we excel in other areas. Close to 100% of all processors
in PCs are designed in the US. When it comes to bare bones electricity
gear and distribution things are more, ahem, kludgy. There are power
poles around here where sag and leaning make me take a little detour
when walking our dogs. Sometimes I used to call utilities about one or
the other situation and they didn't do anything.

--
Regards, Joerg

http://www.analogconsultants.com/

Al wrote:
In article ,
"Paul Hovnanian P.E." wrote:

Joerg wrote:
Paul Hovnanian P.E. wrote:
Joerg wrote:
Al wrote:
In article ,
"Paul Hovnanian P.E." wrote:

Al wrote:
Any ideas as to why my son's electric hot water heater electrode
burned
open? It was cathastrophic! The electrode was replaced and all is OK.

Al

[Image]
The way that the entire element is curved makes me think that it was
severely overheated (probably run dry) at some time.

If the insulation were to fail at one point on an otherwise intact
element, the damage would probably be localized to that one spot.
I think you're right. As far as I know, it was the only one to fail in
that condo complex so early, but still after the warranty expired.
Grrr!

There should have been a thermo-switch preventing overheating. Should
have ... maybe pick a better brand next time you need one. Heck, even
our little hot water dispenser has that secondary protection. Ok, that
one is non-resettable but still $1.50 for a thermo-fuse sure beats $150
for a heater.
Problem: The overtemp thermo switches are mounted on the tank near the
element. They will react to an overtemp condition with a full tank
properly. But the element hanging in air will need to reach a very high
temperature in order to conduct enough heat along its length to the tank
in order to trip the safety switch.

On ours it was mounted right at the root of the element. That location
would get hot really fast if there wasn't any water.
That's a better design than ours. So how did we come to be the sole
remaining superpower in the world with such crappy engineering?


Yeah, and we've been building cars for over a hundred years and they
still have failures and poor ergonomics. And they are designed all over
the world crappily. (Is that a word?)


Not the Japanese ones. Failure rates on both our Mitsubishi and the
Toyota in 10 years: Zero. Not the slightest hick-up.

--
Regards, Joerg

http://www.analogconsultants.com/

Joerg wrote:

Paul Hovnanian P.E. wrote:
Joerg wrote:
Paul Hovnanian P.E. wrote:
Joerg wrote:
Al wrote:
In article ,
"Paul Hovnanian P.E." wrote:

Al wrote:
Any ideas as to why my son's electric hot water heater electrode burned
open? It was cathastrophic! The electrode was replaced and all is OK.

Al

[Image]
The way that the entire element is curved makes me think that it was
severely overheated (probably run dry) at some time.

If the insulation were to fail at one point on an otherwise intact
element, the damage would probably be localized to that one spot.
I think you're right. As far as I know, it was the only one to fail in
that condo complex so early, but still after the warranty expired. Grrr!

There should have been a thermo-switch preventing overheating. Should
have ... maybe pick a better brand next time you need one. Heck, even
our little hot water dispenser has that secondary protection. Ok, that
one is non-resettable but still $1.50 for a thermo-fuse sure beats $150
for a heater.
Problem: The overtemp thermo switches are mounted on the tank near the
element. They will react to an overtemp condition with a full tank
properly. But the element hanging in air will need to reach a very high
temperature in order to conduct enough heat along its length to the tank
in order to trip the safety switch.

On ours it was mounted right at the root of the element. That location
would get hot really fast if there wasn't any water.

That's a better design than ours. So how did we come to be the sole
remaining superpower in the world with such crappy engineering?


I guess because we excel in other areas. Close to 100% of all processors
in PCs are designed in the US. When it comes to bare bones electricity
gear and distribution things are more, ahem, kludgy. There are power
poles around here where sag and leaning make me take a little detour
when walking our dogs. Sometimes I used to call utilities about one or
the other situation and they didn't do anything.

That's maintenance, not engineering. I doubt the field engineer spec'd
the poles leaning 2' out of plumb.

On the other hand, its getting difficult to find any electrical power
gear designed and/or made in the USA. I keep running into Siemens,
Square-D, etc.

--
Paul Hovnanian
------------------------------------------------------------------
It is not enough to succeed. Others must fail. -- Gore Vidal

Paul Hovnanian P.E. wrote:
Joerg wrote:
Paul Hovnanian P.E. wrote:
Joerg wrote:
Paul Hovnanian P.E. wrote:
Joerg wrote:
Al wrote:
In article ,
"Paul Hovnanian P.E." wrote:

Al wrote:
Any ideas as to why my son's electric hot water heater electrode burned
open? It was cathastrophic! The electrode was replaced and all is OK.

Al

[Image]
The way that the entire element is curved makes me think that it was
severely overheated (probably run dry) at some time.

If the insulation were to fail at one point on an otherwise intact
element, the damage would probably be localized to that one spot.
I think you're right. As far as I know, it was the only one to fail in
that condo complex so early, but still after the warranty expired. Grrr!

There should have been a thermo-switch preventing overheating. Should
have ... maybe pick a better brand next time you need one. Heck, even
our little hot water dispenser has that secondary protection. Ok, that
one is non-resettable but still $1.50 for a thermo-fuse sure beats $150
for a heater.
Problem: The overtemp thermo switches are mounted on the tank near the
element. They will react to an overtemp condition with a full tank
properly. But the element hanging in air will need to reach a very high
temperature in order to conduct enough heat along its length to the tank
in order to trip the safety switch.

On ours it was mounted right at the root of the element. That location
would get hot really fast if there wasn't any water.
That's a better design than ours. So how did we come to be the sole
remaining superpower in the world with such crappy engineering?

I guess because we excel in other areas. Close to 100% of all processors
in PCs are designed in the US. When it comes to bare bones electricity
gear and distribution things are more, ahem, kludgy. There are power
poles around here where sag and leaning make me take a little detour
when walking our dogs. Sometimes I used to call utilities about one or
the other situation and they didn't do anything.

That's maintenance, not engineering. I doubt the field engineer spec'd
the poles leaning 2' out of plumb.


Specifying a wooden pole at all is in many cases already an engineering
flaw. I have seen poles that began to look lousy very few years after
being placed. Every engineer out here who does that should take a look
under the deck of an older house. That would cure them.

Then they strung new wires about half a mile from here at a location
where there is a huge digger pine. It has already shed a humongous
branch, is very obviously quite sick, is oozing sap and leaning. Towards
the HV lines. Pathetic.


On the other hand, its getting difficult to find any electrical power
gear designed and/or made in the USA. I keep running into Siemens,
Square-D, etc.


Same here, mostly ABB. I guess Square-D used to be domestic and is now
Schneider.

--
Regards, Joerg

http://www.analogconsultants.com/