Immersion Issues

Guill

We built a house last year and have had issues with our immersion, can anyone shed some light?

The first 3kw Immersion heater blew about 3 weeks after we moved in, by blew I mean constantly tripping the ELCBO. I found it strange and asked an electrician to have a look, he said it needed to be replaced.

It was coming into winter then so we didn't need to change it out straight away as the central heating kept the water hot.
We finally replaced it in February and there was no visual damage on the one we removed. Then the second immersion blew after 1 week. The electrician said at the time that this can happen and we just have to get a new one.

Soon after this the pump in our well, probably 20 years old, started tripping the ELCB too and we had to change it. Once change I decided to try the immersion again and it ran without issue for 3 months, the longest we ever had it going.

It started tripping again at the weekend and I got the electrician out as I feel something funny is going on. Again he tested the immersion and said it was gone. He could not explain why it came back for so long but has recommend we stick in a new, third, immersion.
He also said that us having it on 30 minutes in the morning and 30 minutes in the evening was way too long for an immersion and no immersion would work under that load.

I have lived in many houses and even the last one I lived in relied solely on an immersion heater and we had no issue for 6 years.

Any thoughts on this?

Thanks.

K.Flyer

Guill wrote: »

We built a house last year and have had issues with our immersion, can anyone shed some light?

The first 3kw Immersion heater blew about 3 weeks after we moved in, by blew I mean constantly tripping the ELCBO. I found it strange and asked an electrician to have a look, he said it needed to be replaced.

It was coming into winter then so we didn't need to change it out straight away as the central heating kept the water hot.
We finally replaced it in February and there was no visual damage on the one we removed. Then the second immersion blew after 1 week. The electrician said at the time that this can happen and we just have to get a new one.

Soon after this the pump in our well, probably 20 years old, started tripping the ELCB too and we had to change it. Once change I decided to try the immersion again and it ran without issue for 3 months, the longest we ever had it going.

It started tripping again at the weekend and I got the electrician out as I feel something funny is going on. Again he tested the immersion and said it was gone. He could not explain why it came back for so long but has recommend we stick in a new, third, immersion.
He also said that us having it on 30 minutes in the morning and 30 minutes in the evening was way too long for an immersion and no immersion would work under that load.

I have lived in many houses and even the last one I lived in relied solely on an immersion heater and we had no issue for 6 years.

Any thoughts on this?

Thanks.

There is something up for sure, or you are very unlucky.
New immersion heaters don't seem to last as long as ones from years ago, but you should be getting much longer than that out of them.
As for your electrician saying that 30mins is too long to have the immersion on for as its not designed for the load, makes me think you need a new electrician.
Electric only cylinders usually run the off-peak immersion anything from 3 to 5 hours during the night to heat the water, there are thousands of them out there. Some are 10 plus years old on the original immersion heater going up to 5 hrs a night.

Wearb

I think this will be better suited to the electrical forum.

Bruthal

A dedicated RCBO for the immersion might be an idea to try, assuming the RCD that does all the sockets as well, is what is tripping here.

Sleeper12

Bruthal wrote:

A dedicated RCBO for the immersion might be an idea to try, assuming the RCD that does all the sockets as well, is what is tripping here.

Is an rcbo required by law on new installation? For an immersion?

Andrea B.

Hi.
I would look at the 2 issues seperately first.
Some points to consider and give us more food for thought.
1. Is it possible the stat is set too high and the thermal trip is all that is gone on immersion.
There are different disciplines of electricians wrt to experience and competence.
Further, yes, I have seen qualified individuals who would be challenged with metering out something such as an immersion.
The "30 minute" statement raises a red flag.
2. It should not be possible in a correct plumping set up, but is there any possibility that cylinder water level is dropping?
It would take at least 2 faults to occur; eg. Header water tank emptying + a leak internally to heating coil.
Have you knowledge of the previous lifetime of immersions b4 you moved in?
3. Is it a bath/sink element and if so are both legs blown b4 they were replaced?

The Red Ace

when water is being heated by a second source especially by a back boiler or solid fuel range water temps can go up to near boiling point at times which will be beyond the range of the thermal cut out that are now fitted to immersions, they can usually be re set but when open circuit the immersion wont heat, the pipe stat that controls the circulating pump would need to be set at c 65/70c to stop this happening