Immersion Element tripping ELCB

smorley

I have had to replace my immersion element twice in 10 years. When it fails it starts to trip the ELCB. The attached image shows the most recent failed element. It appears that the bath element has burst the copper tube in a number of locations. The sink element is black in colour unlike the bath element. It is the sink element that is used 95% of the time.

I would like to know what is the underlying cause of the problem that causes the element to fail more often that I would expect and if there is anything I can do about it.

Irish Fire

Lime in the water

SparKing

Depends whether you have an alternative means of heating the water in the cylinder. It seems a little too often to be changing it tbh.
You could replace it with titanium element instead, it doesn't seem to be too covered in Lime either so I'd say it's probably just normal wear and tear.

Outkast_IRE

ya i would imagine your water supply is from a well?
if it is it would probably be worth getting a sample sent of to check its properties .

gyppo

Irish Fire wrote: »

Lime in the water

+1.
This will eventually cause a pinhole to appear on the surface of the immersion element, allow water into the heating coil of the element, and cause an earth leakage current, which trips your elcb.


edit - have you chipped off limescale from the small element?

heinbloed

Is a sacrificial electrode installed?
The absence of lime deposits in combination with the green oxyde layer indicate acetic water.

smorley

gyppo wrote: »

+1.
This will eventually cause a pinhole to appear on the surface of the immersion element, allow water into the heating coil of the element, and cause an earth leakage current, which trips your elcb.


edit - have you chipped off limescale from the small element?

The elment is exactly as it was after removing from the tank.

If I have bad limescale wouldn't the element be caked in it?

Is there anything I can do or is 5 years the expected lifetime?

heinbloed

Test the ph value of the water. Kits are available from the garden center, the pet shop, the drug store or the plumbing center.

yoshytoshy

The immersion looks like it burst ,that usually happens when the immersion is used a lot.
Check your wiring aswell ,make sure you've got good connections.

That larger part is burst on yours ,so I'd say thats been used the most.

smorley

yoshytoshy wrote: »

The immersion looks like it burst ,that usually happens when the immersion is used a lot.
Check your wiring aswell ,make sure you've got good connections.

That larger part is burst on yours ,so I'd say thats been used the most.

The one that is burst is the bath element which is used about 5% of the time.

smorley

heinbloed wrote: »

Test the ph value of the water. Kits are available from the garden center, the pet shop, the drug store or the plumbing center.

If the results of a test is that the water is asidic what do I do then?

meercat

replace the immersion with a stainless steel type
a bit more expensive but it will last longer no matter what type of water you have
your plumber can sort you out

Fujitsu10

smorley wrote: »

If the results of a test is that the water is asidic what do I do then?

I also have acidic water, we have a water treatment system fitted which doses the water at the well. Get a water treatment company to advise you. Be sure to get a few prices before you decide.

heinbloed

If the water is acetic the entire plumbing system should be designed to withstand the low ph of it.
Using stainless steel for the immersion restance heating element certainly helps, but for plumbing the plastic pipes are cheaper.
No copper (cylinder!) or brass is suitable in the long term. Acetic water will corrode these and the metal in the drinking water is not welcome.

If the water was acetic from the beginning the original plumber made a mistake. All costs are to be forwarded to him. Incl. those for a medical check of the water consumers.

studdlymurphy

What temp is the thermostat on the element set to is it at its maximum? Its up to everyones own preference what temp to set it to but I have mine set to 60-65

Hootie

Smorley, Just came across your post. I am having same problem but my tank is taking an hour to hour and half after turning on before it trips the eclb. Did yours trip immediatly over over a time period? I am trying to narrow down if element or thermostat issue. Also how did you get the element out, I see a hugh hex at top of tank.

smorley

Hootie wrote: »

Smorley, Just came across your post. I am having same problem but my tank is taking an hour to hour and half after turning on before it trips the eclb. Did yours trip immediatly over over a time period? I am trying to narrow down if element or thermostat issue. Also how did you get the element out, I see a hugh hex at top of tank.

In my case it tripped just as the element was switched on.

I got a plumber to change the element.