Stopping Immersion Tripping

uch

Lads anyone any advice on stopping the immersion tripping?, got solar in last year and replaced the tank and element to stainless tank and new element, when we get a good sunny day the immersion trips and I have to click the little reset button, it's set to roughly 60 degrees, would adjusting the temperature help in any way?

Wearb

Either the immersion thermostat is faulty or bypassed, or faulty overheat thermostat.

Is the hotwater very hot?

uch

https://www.boards.ie/discussion/comment/123613093#Comment_123613093

Yep the hot water does get very hot, it would scald you at it's hottest, element is only a year old, would it be common for them to fail so quick

Wearb

Has it always been like that..scalding hot.

It's rare for either stat to give trouble. Wired wrongly is more frequent.

You could try turning the stat all the way up and all the way down and then put it back to slightly over 60.

Take a clear photo when you have the cover off and post it here. Remember that you're potentially dealing with mains voltage.

uch

To be honest we got the solar installed in the Feb but only started happening in the sunnier months, June July Aug, then stopped, but started again this June and july, I'll get a pic, but I noticed when I took the cap off to reset that there was a cut wire, not disconnected, cut with a snips, would this be the issue?

Sorry should have said yes it was always very hot if we got more than 4 hours of sunshine

uch

immer.jpg

Sorry cant link to it for some reason

https://imgur.com/a/5mstXtC

Wearb

It's very difficult to see but it seems to be correctly wired (I can not be certain). Check that the other end of the black wire isn't connected to anything. Try what I said with the stat.

If that doesn't work, I'd advise getting an electrician to have a look. It's just too difficult to be sure of that wiring without being there to have a poke around.

Markus Antonius

What's controlling the power to the element? I manually control mine (not connected to solar) and it will trip if someone forgets to turn it off.

uch

https://www.boards.ie/discussion/comment/123613407#Comment_123613407

It's the solar I have an eddi and I think a harvi, not sure about names and they feed into heating the tank

Wearb

Do you have pv panels or tubes? I assumed pv.

Orban6

https://www.boards.ie/discussion/comment/123613287#Comment_123613287

Can't help with the tripping issue but the snipped wire may be for a dual element heater.

Lenar3556

https://www.boards.ie/discussion/comment/123613407#Comment_123613407

It shouldn’t.

Lenar3556

https://www.boards.ie/discussion/comment/123613341#Comment_123613341

wiring looks ok.
Suggest changing the stat.
Is there any other heat source heating the cylinder other than this element? Oil boiler? Solid fuel stove?

greasepalm

I have solar thermal panels that got serviced today to give me hot water once again.

My element does not work in the immersion due to a short and needs replacing and switched off.

On your photo do i see your thermostat pointer over the max desired temp, Did you try switching it off at the wall as dont need it for heating water with thermal panels.

Google your element details and look at other photos to see if someone upped it to maximum?

con747

https://www.boards.ie/discussion/comment/123613601#Comment_123613601

The OP said they have an Eddi & Harvi so it would suggest they have solar pv panels not thermal panels.

John.G

I have a theory (for what its worth) that if you leave a top mounted immersion switched on always, that even with a perfectly functional thermostat that the final temperature will only reach its setpoint on the cylinder's first heating from cold, on heating from cold the temperature rise through the whole (element) cylinder length will be uniform so the stat is measuring a uniformly average temperature so will cut out at 60C, assuming a present 19C cold mains, then if ~ 76% vol of the HW is drawn off then the stat will cut back in as the average measured stat temp will be 50C (assuming 10C hysteresis), the next reheat will then result in 76% at 74C and 24% at 19C when the stat cuts out at a average of 60C. If the next draw off of HW is greater than this "76%" then the HW temp will be still higher. Of course what invalidates this theory is that even if it operates as I suggest that the Hi limit trip "average" should presumably work the same way as the control stat since its part of the same rod type thermostat. I did see a top mounted immersion with a separate hi limit stat bolted to the top of the immersion (quite common prior to the combined stat) and wired internally with the control stat, this will measure the hottest temperature and trip even if the average control stat temp is below 60C, this immersion did occasionally trip as well despite changing both the control stat and the hi limit stat a number of times.

I suppose someone with a top mounted stat can easily see if the HW outlet temperature does actually vary by draining off say 60% of the contents to get the stat to cut in and then measure the HW temperature after it again cuts out.

uch

https://www.boards.ie/discussion/comment/123613421#Comment_123613421

PV panels

Wearb

https://www.boards.ie/discussion/comment/123613840#Comment_123613840

Is that all that you have heating the cylinder at the moment, pv panels feeding the immersion element?

Have you tried my suggestion?

uch

https://www.boards.ie/discussion/comment/123613863#Comment_123613863

Yep only solar heating the cylinder, the Gas central heating can also heat it but that hasn't been turned on in months

I'll try your suggestion tomorrow when I'm working from home and can keep an eye on it, thanks for all the advice

greasepalm

How can an immersion trip if not powered on is confusing me , and the dial up so high on the photo .

John.G

If you mean the stat SP temp. the arrow is set to just about 60C.

greasepalm

https://www.boards.ie/discussion/comment/123614953#Comment_123614953

Whatever way the light was on it i only saw the arrow on the high side as did wonder as all others seen clearly.

uch

https://www.boards.ie/discussion/comment/123614892#Comment_123614892

It's powered by the Solar

John.G

It doesn't matter what's powerimg it as long as its fed through the thermostat, when the stat measures a average temperature of 60C, then, it switches off the power, if solar derived power then the excess is diverted back to the grid.