Immersion heater tripping electrics

[Mary1]

For the last two nights my electric sockets have all tripped in the middle of the night and I have narrowed it down to my immersion heater on my tank. This morning with everything bar fridge switched off , I set the timer on immersion and waited, immersion didn't seem to come on as there were no lights or noise, but at end of time that time was set to (if that makes sense) the trip switch went, it wouldn't switch back on, so I switched immersion off and then trip switch back, so all sockets working again, then I switched immersion back on and it tripped! I have a grasslin ecosave timer. I know I will need an electrician, but if anybody could suggest anything I could try to narrow it down anymore before calling one,or what could be the possible causes so that I'm not completely clueless when electrician arrives! Also, I've got no idea how to find a reputable company??? I'm having a bad time at the moment with a new kitchen fitting that's gone wrong too and have been badly ripped off (but that's for another post) so really reluctant to get anybody out... thank you in advance

 

[winston1]

If the immersion heater needs replacing (sounds like it) a plumber may be more appropriate.

 

[JohnD]

it probably tripped once the water in the cylinder had cooled enough for the thermostat to turn the heating element back on.

You might have two faults:

- an old immersion heater element where the insulation has broken down due to great age

- some other fault which also has earth leakage

And only when the two (or more) occur at the same time does the earth leakage, added together, reach a high enough level to cause the trip.

For a better idea of what's happening, please attach a photo of the hot water cylinder, the wires and conrols around it, and the top cap of the immersion heater element

and of your consumer unit, with the flap open, showing all the breakers, and a closeup showing the one that tripped

thanks

p.s.
to find a plumber or electrician, a personal recommendation of a local person, by someone you trust, is a hundred times better than an internet search on an advertising website disguised as a recommendation site.

For electricians, you can look up qualified people on one of the self-certification membership sites such as
https://www.niceic.com/householder/find-a-contractor

 

[Mary1]

If the immersion heater needs replacing (sounds like it) a plumber may be more appropriate.

Thanks yes that was what I was just reading I suppose as long as I can find a plumber that can test the electrics first before removing the the parts and just replacing

 

[Mary1]

it probably tripped once the water in the cylinder had cooled enough for the thermostat to turn the heating element back on.

You might have two faults:

- an old immersion heater element where the insulation has broken down due to great age

- some other fault which also has earth leakage

And only when the two (or more) occur at the same time does the earth leakage, added together, reach a high enough level to cause the trip.

For a better idea of what's happening, please attach a photo of the hot water cylinder, the wires and conrols around it, and the top cap of the immersion heater element

and of your consumer unit, with the flap open, showing all the breakers, and a closeup showing the one that tripped

thanks

p.s.
to find a plumber or electrician, a personal recommendation of a local person, by someone you trust, is a hundred times better than an internet search on an advertising website disguised as a recommendation site.

For electricians, you can look up qualified people on one of the self-certification membership sites such as
https://www.niceic.com/householder/find-a-contractor

Thank you I will get photos now. I just touched the end of the elements on the tank and the top economy 7 one is hot to the touch would that mean anything?

 

[Mary1]

Thank you I will get photos now. I just touched the end of the elements on the tank and the top economy 7 one is hot to the touch would that mean anything?

 

[JohnD]

It might mean it has recently been heating up, but it could also be that the hot water is transmitting heat to it. It should not be hotter than the water.

Earth leakage faults can be very difficult to track down so if you want to investigate an experienced qualified electrician would be better than a plumber. On the search page you can see who is a Contractor and who is a "domestic installer" which is a lower grade. If you can see how long they've been in business that means you can get an experienced one.

When we see the pics we can make a guess if changing the immersion element is likely to fix the problem. It's probably the cheapest and quickest thing to do.

 

[Mary1]

Hope pictures uploaded

 

[JohnD]

the yellow insulation tells me the cylinder is around 30 years old. Newlec is an own brand of element. Nothing obvious about it. Please show the cable too.

The bottom element should be the Economy 7 one.

edit
was it the RCD above the green label that tripped?

the CU is a good brand and the installation looks good, nothing obviously suspicious there. Not very modern, but perfectly reasonable. You could try turning off the shower at the ceiling cord switch (after turning it off at the shower itself) and see if that makes any difference. Earth leakage faults are most often found in watery things.

 

[Mary1]

Hope pictures uploaded

Forgot this one

 

[JohnD]

have you got two consumer units?

 

[Mary1]

the yellow insulation tells me the cylinder is around 30 years old. Newlec is an own brand of element. Nothing obvious about it. Please show the cable too.

The bottom element should be the Economy 7 one.

edit
was it the RCD above the green label that tripped?

the CU is a good brand and the installation looks good, nothing obviously suspicious there. Not very modern, but perfectly reasonable. You could try turning off the shower at the ceiling cord switch (after turning it off at the shower itself) and see if that makes any difference. Earth leakage faults are most often found in watery things.

Here is bottom element it says on peak

 

[Mary1]

Here is bottom element it says on peak

Top element

 

[Mary1]

Here is bottom element it says on peak

Hi John, yes it is the switch above green label. The shower is always switched off with pull cord after use so does that mean it's not that? I'm wondering I'd I should try switching immersion back on and see if it trips again and maybe try boost switch because yesterday I did that and it isn't trip but I'm a bit scared so is it safe to keep testing sidderenr things and I'd it keeps tripping?

 

[JohnD]

looks like the bottom one has been leaking. Possibly the top one too. That might be connected with the tripping. Modern sealing of screwed plumbing, using PTFE, can be much better than old seals, so it may be that fitting new ones will cure it. To change an old immersion element you need an experienced plumber, as they may be stuck and can be difficult to remove without damage. I'd get them both changed at the same time. The cylinder will need to be drained, which the plumber can do. Clean away all marks of leakage afterwards with a green pan scourer, so that any new leak is easy to spot, and people will not see the old marks and think the leak is still there.

Worst case, you might need a new cylinder, for example if the sockets where the elements screw in are corroded or there is some other leak. If you do that, I like to get the biggest one that will fit in your airing cupboard, the cost is not much more than a small one.

BTW it is not correct, and is uneconomical, to connect the bottom element to the Peak supply. It should be the cheap-rate economy supply, controlled by the timer. Follow the route of the cables to check. You can add a red jacket or two to that old cylinder, which will cut heat losses and save you money.