(Covered in a recent tech seminar I went to)

It turns out that having an electric water heater element running in a dry water heater by itself does not burn it up.

The vendors told me that the element itself can run continuously without damage - BUT! There are some , err.... "CAVEATS" to it.

For one thing, as we know, the water heater without any water in it CANNOT sense a change in water temperature until it is too late (much too late...).

We know that, it's a given. But what else happens?

If an electric heater is running full on, without water to cool it, and no shut off from the water temperature sensor it can cause a hot spot directly above it (because heat rises...) that will MELT THE INSULATION OF THE TANK DIRECTLY ABOVE THE ELEMENT. Does this make sense?

And that can ruin the water heater all by itself.

The elements are designed and built to survive running in this condition if nothing else changes.

Now here is the KICKER: If the element is RED HOT, and then suddenly you realise "OH NO! THERE ISN"T ANY WATER IN IT!!!" and fill it UP...

When the cold water hits the cherry red heating element - oxidation and a lot of other wonderful events take place, and that is what causes it to just go "POOF!" and blow to bits...

Now obviously - there are some possibilities in this, and the most interesting to me is this one: If you know an electric element has been running like that (because you spot the switch, or however you notice it) DON'T ADD WATER! Or at least not right away.

SHUT IT DOWN, just turn it off...

Give it a half hour or more to cool back down, and hope the insulation is still undamaged. By doing this, you just might save an abused element (FACT!).

You should then visually inspect the water heater tank for any signs of damage to it, like plasticky stuff bubbling out of the casing.

If all goes well, I have probably saved you some hassles - NOBODY likes a cold shower in the woods! I don't care if you are Croc Dundee himself...

FYI, Gratis

~Wolfie

 

I guess poshoric acid changes that a bit. My parkerizing tank warped and my 1500watt element stoped drawing power and would not heat the tank back up. It seems intact, but I can't get it to heat over 140 degrees.

 

Do an ohms check on it. The manufacturers websites often have specs on what they should read, but if it is zero it's definitely open (and thus, crispy crittered).

140 might be the upper limit though - over that a consumer could come back with a claim for getting burned. I'm assuming you ran it on LPG.

Another thought is that the temp sensor needs replacement because it went too far over it's rated temperature.

In the final analysis it might be cheaper to dispose of it and get a new one, if it is (as you say) visibly warped.

 

I tried it on 12v first, but I wouldn't produce the wattage to get to 180 degrees, so I went AC. On 110ac, the temps shot up quick and stayed close between 18- and 185 for 30 minutes. I got everything I needed parkerized done, so I am happy.

But to add to your tips, sch 40 pvc pipe does not like staying at 180 for any lenght of time. Gravity start to over come a length of it rather quickly.

 

12VDC? In a water heater????

Who makes it?

Something here doesn't sound like it came from planet earth...

And a water heater (standard) for an RV shouldn't be over 156 degrees at all. Sorry - but that ain't right.

 

Great info, Thanks G-wolf