# Wild water heater



## kbsparky (Sep 20, 2007)

Got a service call yesterday, with the lady complaining about scalding hot 
water at the spigot: 

She had already called a plumber who replaced both thermostats not once, but _twice._ Did not solve the problem. Water still gets hotter and hotter until the reset button pops on the heater. 

Also, she noted that one time when she happened to touch the flex conduit that feeds the wiring into the unit, it was hot temperature-wise, and it also shot out some sparks from the fitting at the heater! :001_huh:

Without even looking, I figured out the problem: Bad element, which was using electrolysis to continue heating using the water as a partial return path for the electricity. 

Sure enough, testing showed the upper element had faulted (continuity) to ground.

Here is the weird part: I could NOT unscrew that element! Using a ½" ratchet wrench, with a 1½" socket it would NOT BUDGE!! I have never encountered this.

I figure that the electrolysis somehow welded the threads of the element to the tank. I can't come up with any other explanation .... :blink:

I ended up leaving the bad element in place. Disconnected all the wiring from the upper element, and configuring the lower element for exclusive heating of the tank. Besides, that upper element only operates maybe 5% of the time, with the bulk of the water heating duties being done by the lower one. Heck, even my own water heater in my house only has one (lower) element! :whistling2:

So far, so good! Her water heater is now operating normally. If she can get another year or 2 out of it, then she'll be a happy camper.


----------



## Vintage Sounds (Oct 23, 2009)

Electrolysis continuing to heat the water? Does that mean the thermostat only breaks one leg to turn off the element?


----------



## niteshift (Nov 21, 2007)

Ever see the mythbuster episode where they launch a waterheater. 
From the basement up thru 1st, 2nd floors, out the roof and continued on a flight path to a spot about 500' away.

Water is still the baddest mo fo, if you don't include weapons.
Bypass all the safety features and you too can launch one.


----------



## wendon (Sep 27, 2010)

Vintage Sounds said:


> Electrolysis continuing to heat the water? Does that mean the thermostat only breaks one leg to turn off the element?


That's correct, unless it trips the reset, then both legs are disconnected


----------



## chicken steve (Mar 22, 2011)

so how is it the lady in question didn't get shocked if the water was a path for power here?

~CS~


----------



## hardworkingstiff (Jan 22, 2007)

Vintage Sounds said:


> Electrolysis continuing to heat the water? Does that mean the thermostat only breaks one leg to turn off the element?


Yes, that's the way everyone I've seen works.


----------



## McClary’s Electrical (Feb 21, 2009)

chicken steve said:


> so how is it the lady in question didn't get shocked if the water was a path for power here?
> 
> ~CS~


 
Had she touched something grounded at the same time as the running water, she might have been. Most likely plumbing fixtures, pipes and sinks were all at the same potential


----------



## Big John (May 23, 2010)

chicken steve said:


> so how is it the lady in question didn't get shocked if the water was a path for power here?


 Sounds like a very localized path: The good grounding of the pipes/tank/whatever was enough to shunt away most of the voltage and what was left wasn't enough for her to get a shock, luckily. 

Similar to how you can touch a loaded neutral conductor without (usually) getting bit.

-John


----------



## kbsparky (Sep 20, 2007)

chicken steve said:


> so how is it the lady in question didn't get shocked if the water was a path for power here?
> 
> ~CS~


The path within the water went from the exposed element through the tank, and then thru the metal flex conduit.

When she touched the metal flex, its connection at the base of the connector was marginal, and sparks flew. Since she was standing on a wooden floor, and not touching any other grounded surface, no shock was realized.

But the shock of seeing sparks fly, as well as the feeling the elevated outer temperature of the flex was enough for her! :blink:


----------



## chicken steve (Mar 22, 2011)

ok, so i would imagine some bonding would be appropos here....?

~CS~


----------



## kbsparky (Sep 20, 2007)

Yup. I installed a nice green wire into that flex, bonding both ends to eliminate the flex from being an inadvertent conductor should the other element suffer the same fate .... :thumbup:


----------



## chicken steve (Mar 22, 2011)

ah, _good man_ KB

i've been doing a lotta reno's lately where the older wiring is fairly erroded, or old and ungrounded, so bonding is always on my mind....~CS~


----------



## Shockdoc (Mar 4, 2010)

Was the pressure relief valve exhausting any water ? Or was rigged to stay closed?
Sounds more like a handyman repair the first time around.


----------



## chicken steve (Mar 22, 2011)

lot of 'em replaced by plumbers never realize that changing out to plastic has it's electrical implications.....~CS~


----------



## B4T (Feb 10, 2009)

niteshift said:


> Ever see the mythbuster episode where they launch a waterheater.
> From the basement up thru 1st, 2nd floors, out the roof and continued on a flight path to a spot about 500' away.
> 
> Water is still the baddest mo fo, if you don't include weapons.
> Bypass all the safety features and you too can launch one.


They did it by disconnecting the press relief valve.. just wanted to throw that in there..


----------



## user4818 (Jan 15, 2009)

B4T said:


> They did it by disconnecting the press relief valve.. just wanted to throw that in there..


And the thermostat as well. :whistling2:


----------



## BBQ (Nov 16, 2010)

FWIW, there are


The regular T stat

The high limit T stat

The Temperature and Pressure valve which releases at 210F or 150 PSI whichever happens first.

All have to fail or be bypassed / plugged to get an explosion.:nerd::nerd:


----------



## erics37 (May 7, 2009)

niteshift said:


> Ever see the mythbuster episode where they launch a waterheater.
> From the basement up thru 1st, 2nd floors, out the roof and continued on a flight path to a spot about 500' away.
> 
> Water is still the baddest mo fo, if you don't include weapons.
> Bypass all the safety features and you too can launch one.





B4T said:


> They did it by disconnecting the press relief valve.. just wanted to throw that in there..





Peter D said:


> And the thermostat as well. :whistling2:


All that turns it into a regular boiler :thumbup:


----------



## niteshift (Nov 21, 2007)

erics37 said:


> All that turns it into a regular boiler :thumbup:


More like a pressure cooker.:laughing:


----------



## big vic (Jan 23, 2012)

She could have bought a new water heater instead of paying for two service calls from a plumber and one from an electrician. Especially since she still hasn't got anything fixed correctly


----------



## user4818 (Jan 15, 2009)

BBQ said:


> All have to fail or be bypassed / plugged to get an explosion.:nerd::nerd:


You got the :nerd: part right.


----------



## kbsparky (Sep 20, 2007)

Shockdoc said:


> Was the pressure relief valve exhausting any water ? Or was rigged to stay closed?
> Sounds more like a handyman repair the first time around.


The hi-limit switch cut it off. Water got scalding hot, then popped the reset button, and then it would cool off over the next several hours.

The "handyman" aspect is due to the plumbers trying to be electricians.



big vic said:


> She have bought a new water heater instead of paying for two service calls from a plumber and one from an electrician.
> 
> Especially since she still hasn't got anything fixed correctly


 hindsight is always 20/20.

Who are you to say nothing is fixed correctly?

I believe that she paid the plumber once, and his return trip was free. Once it was determined that he failed to repair it properly, I was called in to check it.

Customer reports that the water heater is working fine now. No more scalding hot water, and reasonable hot temperature from the faucets.


----------

