Thread: Black soot/staining on electric water heater?

What would cause the black above the TPR on a electric water heater?

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Likely burnt wires to the thermostats.

it's 19 and Smokin!!!!

It is way beyond the SOP to do this, but a neat trick is to use your power or multibit screwdriver to remove the covers over the thermostat connections. The screws are usually hex heads same size as the bit driver, 1/8" hex, I think they are.

Turn off power momentarily, and don't do it if you are not mechanically inclined.

I will do so if there is rust staining in that area. Sometimes the element will leak around the seal.

The soot could be from burning wires, or could be from a past short that was repaired. Is the breaker sized correctly for the the unit and the supply cable?

For me, this is a case of throwing the SOP out the window and I do not like deferring to a contractor when it is something for which I should have some knowledge and I feel comfortable making my own evaluation. Being the curious person, I want to know or least try to know what caused this. I do have a high mechanical aptitude and experience with and respectful of electricity.

I would take the covers off including the electric connection box, to investigate. All within reason; I'm not taking WH apart. Even if it was old and needed to be replaced, I hopefully would learn something so the next time I saw it I would know what was a likely cause.

I'll probably be lectured on this post but that's okay. This is MY approach and likely wouldn't be recommended to a lot of people.

Hi, ALL &

Speaking of "electrical", where is the armoured cable /BX ?

Forgive my CANADIAN spelling...

Have a Great long-weekend (B. C. Residents) & keep on enjoying Summer !


Cheers

Originally Posted by Glenn Duxbury

Hi, ALL &

Speaking of "electrical", where is the armoured cable /BX ?

Forgive my CANADIAN spelling...

Have a Great long-weekend (B. C. Residents) & keep on enjoying Summer !


Cheers

FMC is not always required in the US. The NM cable has to be protected from inadvertent damage but it depends on the location of the WH and access to it. Most good contractors will still place the NM cable in FNMC or FMC to where the cable runs to the wall framing (in unfinished areas) or ceiling.

Originally Posted by Stuart Brooks

FMC is not always required in the US. The NM cable has to be protected from inadvertent damage but it depends on the location of the WH and access to it. Most good contractors will still place the NM cable in FNMC or FMC to where the cable runs to the wall framing (in unfinished areas) or ceiling.

In Canada, flexable conduit is always required except if it is a manufactured (mobile) home. People will stack their junk on a water heater, like a sharp pair of ice skates, and we all wear ice skates up here.

But we don't need to fill our houses withn AFCI's, so y'all got us beat on that one.

The cone of black particulate above the TPR valve is soiling caused by the convective heat plume off the TPR itself. As room air gets heated by this chunk of brass protruding from the insulated shell of the appliance, it creates a draft right up against the metal cabinet. There, soils of any sort, whether actual soot, dirt, skin cells,- whatever can deposit. On gas WHs you need to consider whether or not this particulate is coming up from the combustion chamber below vs. from the ambient room air. On some units you will find heat and soot tracks down at the combustion chamber indicating spillage. Add this to the conditions at the draft hood and nipple bushings to consider flue gas spillage on gas units.