Immersion Heater Overheating & Kettling

[stephen1974]

Hi All,

My nans hot water recently stopped working which resulted in an extremly over priced plumber coming out and replacing both elements in the immersion tank. Aside from a huge price tag, it seemed the issue was resolved... until a few weeks back

The cut off switch keeps going off if the heater is left on for more than a couple of hours and there is a kettling sound coming from the tank within seconds of the heating turning on. The elements have been changed a second time now but the over heating and kettling persists.

The plumbing company we used isnt interested in trying to fix it - I dont think they have a clue what the problem is, so its a time consuming unpaid ball ache for them.

What could be the possible cause(s)

 

[Deleted member 120897]

Do you have 2 issues or just the 1? You’ve mentioned when the heating is on that kettling occurs, but then have mentioned elements and kettling persisting? 🤔

Does she live in a hard water area?

 

[snowhead]

Have you got a picture of the cylinder and the Immersion heater(s) location(s)?
Has it got 1 or 2 immersion heaters?
Do you know if it's vented or unvented, if unvented it will have more valves and pipes around it.

It seems like the thermostat, within the immersion, if it's and old style normal vented cylinder, is most likely set too high and causing the overheat control to trip.

 

[stephen1974]

Im assuming its one issue producing two symptoms, the kettling and the switch going off.

Dont have a picture, its a large cylinder, however, i would say its very similar to this one.

The
plumbers claim to have set the thermostat correctly.

 

[John.g]

Can you switch off power to the heating element(s), remove cover(s) and post a few photos, you can also note the thermostat setting(s).