On peak off peak wired incorrectly?

[MeganS]

Hi
Absolutely 0 knowledge of this so excuse language / terms / explanation.

Electric only ground floor 2 bed flat ( 3 external walls)

On peak and off peak switches for immersion (water in a tank…goes to kitchen sink , shower , toilet and bathroom sink) - to note - this water is boiling hot - have turned thermostat down multiple times, think we’re on around 30c now????
If I turn ‘ON peak’ switch off & leave just ‘OFF peak’ on we end up without any hot water to sinks and electric shower.

On and off peak switches for storage heater. If I turn ‘ON peak’ switch off, this turns the power off to the storage heater (this is wrong, am I right?) which inevitably then leaves the ‘OFF peak’ switch irrelevant and it’s not doing anything.

Please please please can someone help me with this. I have absolutely no knowledge, I have had 4 electricians round my house and none of them can solve this issue (is it for plumber or electrician or combined???)
My bill is absolutely sky rocketing (not just due to increases as it was this way when I moved into the property 2 years ago and I have tried multiple times to solve) to put this into context I am being billed approx. £350 a month for a 2 bed ground floor flat…. This has been before the price increases also, since 2020 when we moved here and again I should add during winter months so problem kid mainly with storage heaters I believe but also immersion on peak off peak is wrong I believe.
EON refusing to help - say not their fault?
Paying ‘call out’ charges to electricians who cannot help…
My house is becoming covered in mould as I cannot keep up with the bill to heat my home and ventilate it correctly (too cold now with winter and a waste of the heat)
Thanks

 

[baldelectrician]

Some pictures of the current aet up would help

Without taking any covers off consumer units etc can you photograph your consumer unit and meter set up and post it online?

Several would be good
Close up and from a distance

 

[snowhead]

As above and also pictures of the wiring to the storage heater(s) with the On and Off peak switches.

To add, the storage heaters if supplied with On and Off peak only use the On peak for the controls and need both On and Off peak turned on to be able to work.

If the Hot water is getting to to 30c, there's either a fault with the thermostat, or it's set too high, within the immersion heater.
Even if the heater was left on 24/7 and you didn't use any Hot water the water should never get above 60c, if set correctly

 

[littlespark]

Do you have an actual off peak tariff with your supplier? Your bill should have 2 rates.

 

[MeganS]

Some pictures of the current aet up would help

Without taking any covers off consumer units etc can you photograph your consumer unit and meter set up and post it online?

Several would be good
Close up and from a distance

Some pictures of the current aet up would help

Without taking any covers off consumer units etc can you photograph your consumer unit and meter set up and post it online?

Several would be good
Close up and from a distance

Hoping this is what you’ve asked for…? Sorry I’m pathetic when it comes to this
I also don’t have an Allen key to hand to open up my meter outside
Will try by the end of today, will ask a neighbour to open
Thanks for your reply

 

[MeganS]

Do you have an actual off peak tariff with your supplier? Your bill should have 2 rates.

Thank you - Yes I do , see photo attached. This is another reason for my confusion. When I base my calculations off of these tarrif i.e. applicable wattage x hours of usage x p/kWh …. It isn’t adding up… so something somewhere to me is wrong ?

 

[MeganS]

As above and also pictures of the wiring to the storage heater(s) with the On and Off peak switches.

To add, the storage heaters if supplied with On and Off peak only use the On peak for the controls and need both On and Off peak turned on to be able to work.

If the Hot water is getting to to 30c, there's either a fault with the thermostat, or it's set too high, within the immersion heater.
Even if the heater was left on 24/7 and you didn't use any Hot water the water should never get above 60c, if set correctly

Photos attached
Thank you clarifying re storage heaters - to me it seemed wrong that the on peak was on all the time but like you say it’s being used for the control

Still unsure about thermostat as my water is too hot to even touch - we basically have cold showers as it’s generally ‘too hot’ on the middle or high temp on my elec shower.

 

[littlespark]

Is there any other equipment around the consumer unit?
Even cabling? Or is it all come from behind in the wall?

There are two immersion heaters. The lower one should be Off peak... will heat the entire tank overnight on cheap rate.
The higher one is a boost, and will only really heat the water above it, as a 'bit extra' during the day if you need it, controlled by a "Quartz E7" timer or similar that can give you an hour or so of power to the upper immersion during the day on the higher rate.

If its a general 7kW or whatever electric shower, then it would take cold water, and heat it itself. It doesnt need to take water from the hot tank.... A photo of the showers rating plate would help also. (white sticker on top or bottom of unit?)

 

[MeganS]

Is there any other equipment around the consumer unit?
Even cabling? Or is it all come from behind in the wall?

There are two immersion heaters. The lower one should be Off peak... will heat the entire tank overnight on cheap rate.
The higher one is a boost, and will only really heat the water above it, as a 'bit extra' during the day if you need it, controlled by a "Quartz E7" timer or similar that can give you an hour or so of power to the upper immersion during the day on the higher rate.

If its a general 7kW or whatever electric shower, then it would take cold water, and heat it itself. It doesnt need to take water from the hot tank.... A photo of the showers rating plate would help also. (white sticker on top or bottom of unit?)

No it is all in the wall, just the box showing in my porch.

Sorry when you say ‘the power should be off peak’ are you saying mine is wrong given on this photo the bottom one is on peak?
Do u suggest that I switch one of them off? As I am under the impression - like you say - that one of them should be for a ‘boost’ e.g. you have guests and need extra hot water….

Shower sticker attached. Excuse the dirt

 

[littlespark]

Ok.. so if the shower is giving problems with too much or too little heat, then its a problem with the shower itself.
It may be that its too big for the supply RCBO.... but you cant upgrade that unless the cable is big enough.
(9500 / 230v = 41A.... bigger than 32..... )

I couldn't tell by the photo which immersion is connected to which switch.

An electrician should be able to tell which is which, even with a non-contact detector would give a good indication.

Someone may correct me on the following.....

The E10 tariff would mean 7 hours off peak overnight, and another 3 during the day.

Depending how its all set up.... The older systems gave you cheap rate on all your electric overnight.... Newer ones, just the heating.
So the Hall Heater on the 3rd circuit could be on high rate all the time.

There is only 2 storage heaters on the Off peak, so where is the second immersion supplied from?

 

[snowhead]

As L-S above, there isn't a supply labelled for the Off Peak Immersion and there would normally be a controller with time clock set to switch on the lower Off peak imersion on during the off peak hours for 2 or 3 hrs.
As noted above Off Peak is probably 7 hrs overnight and 3 during the day.

Re the water temperature and the thermostats, the lower due to it's location should be around 45c and upper (middle of cylinder) should only be around 50c max, to get 60c at the top.
If the water is still too hot when you have them set at 30c then the thermostats need replacing.

 

[buzzlightyear]

What's the betting the other element is feed from the ring.

 

[MeganS]

Ok.. so if the shower is giving problems with too much or too little heat, then its a problem with the shower itself.
It may be that its too big for the supply RCBO.... but you cant upgrade that unless the cable is big enough.
(9500 / 230v = 41A.... bigger than 32..... )

I couldn't tell by the photo which immersion is connected to which switch.

An electrician should be able to tell which is which, even with a non-contact detector would give a good indication.

Someone may correct me on the following.....

The E10 tariff would mean 7 hours off peak overnight, and another 3 during the day.

Depending how its all set up.... The older systems gave you cheap rate on all your electric overnight.... Newer ones, just the heating.
So the Hall Heater on the 3rd circuit could be on high rate all the time.

There is only 2 storage heaters on the Off peak, so where is the second immersion supplied from?

The shower I’m not too fussed over re cost as it’s not on long enough to lose sleep over although my only concern is that the water is so hot due to the tank being boiled ‘like a kettle’ all day due to the switches being incorrect and the on peak kicking in all day?

I’ve had 4 electricians here and not many are able to tell me the problem, I did have one but he quoted me £10,000 to do a full replacement

For info - I have 3 500W electric dimplex heaters in hallway, room 1 and room 2
1 x XLE 1.5KW dimplex storage heater in living room / kitchen (open plan)

 

[MeganS]

What's the betting the other element is feed from the ring.

Thank you for your reply - I am Not sure what this means but assuming you are talking to the other professionals

 

[James]

Where exactly is the water too hot, sink or shower?

also, where is the thermostat that you are adjusting to change the water temperature?

 

[MeganS]

Where exactly is the water too hot, sink or shower?

also, where is the thermostat that you are adjusting to change the water temperature?

Both

Thermostat adjustment behind these 2 black knobs - circled in green on photos attached.

 

[MeganS]

Found the key for the meter

 

[MeganS]

Some pictures of the current aet up would help

Without taking any covers off consumer units etc can you photograph your consumer unit and meter set up and post it online?

Several would be good
Close up and from a distance

 

[buzzlightyear]

Thank you for your reply - I am Not sure what this means but assuming you are talking to the other professionals

yes, but I have found were some emersion heater are feed from the socket circuit .

 

[Avo Mk8]

Hi MeganS
In relation to the two switches "off-peak" and "on-peak" connected with white wires to the immersion heaters, could you follow the cable from the bottom switch and check if it goes to the bottom or top immersion, and similarly the other cable from the top switch goes to which immersion?
I am puzzled by the fact that the light is lit on the bottom switch - did you take the photo during the day, or at night (or to be more accurate, during 'off-peak)?
It would be good to know if the switches are labelled the right way round, and the above might confirm!

PS photo's of your meter etc helpful thank you!

 

[MeganS]

Hi MeganS
In relation to the two switches "off-peak" and "on-peak" connected with white wires to the immersion heaters, could you follow the cable from the bottom switch and check if it goes to the bottom or top immersion, and similarly the other cable from the top switch goes to which immersion?
I am puzzled by the fact that the light is lit on the bottom switch - did you take the photo during the day, or at night (or to be more accurate, during 'off-peak)?
It would be good to know if the switches are labelled the right way round, and the above might confirm!

PS photo's of your meter etc helpful thank you!

Thank you.
- Off peak switch cable goes to the top knob. - On peak switch cable goes to the bottom knob.

Which would appear correct?

 

[Avo Mk8]

Thank you.
- Off peak switch cable goes to the top knob. - On peak switch cable goes to the bottom knob.

Which would appear correct?

Not in my opinion!
I'm thinking what you call a knob is the cover of each immersion heater, which has the thermostat adjusting knob in it.

The bottom immersion is there to heat the whole tank, and that is the one normally powered by off-peak.
The upper immersion is for a "boost" if you run out of hot, normally fed from on-peak.
Does the light on the on-peak switch actually stay on all the time?

My first thought is that they are wired the wrong way round, but at this time of night I could be wrong. No doubt someone will be along to comment!

 

[marconi]

How far away from the Dartford Crossing is your home?

 

[Avo Mk8]

Following on from my comment above, it still could be that both immersion heaters are running from the on-peak supply, together with the hall heater as mentioned previously. The thermostat in the bottom immersion seems to need attention, all as per Snowhead in post #11, as well as checking that the upper immersion is actually functioning.

 

[Avo Mk8]

So far it appears:

• the 'off-peak' section of the consumer unit seems to be fed from a DNO/Eon contactor, so should actually be 'off-peak'!
• (anybody care to comment on the presumably timed neutral feed to the contactor from meter, what's the other to the Henley?)
• the right hand 'off-peak' MCB position labelled 'immersion' has had the breaker removed
• so we don't know where power for the immersion heaters is now coming from.
• the bottom immersion heater works, but seems to need a new thermostat
• the top immersion heater does not work, but we don't know if it's lack of power, fuse, thermal cutout or faulty element etc.
• the flex to each of the immersion heaters seems to be transposed compared with what you would expect.
• the 3 x 500W Dinplex (presumably panel, not storage) heaters in the hallway are powered from peak rate electricity, which may be correct for that type of heater,

You would think it would be relatively straightforward for a competent electrician to sort this out !

 

[snowhead]

So far it appears:

• (anybody care to comment on the presumably timed neutral feed to the contactor from meter, what's the other to the Henley?)

The meter timed auxiliary contact has N in sourced from the Henley and N sw out to contactor.

It does seem there has been some interference with the original setup, for unknown reasons.

What needs investigating is;

Do both immersion heaters work when powered, if not replace as required,

Do the thermostats in each heater control that heater correctly when set to the appropriate temperature, if not replace as required,

Is the top heater controlled by a switch labelled ON Peak (preferably the upper switch to avoid confusion) which is supplied from the ON peak section of the Consumer unit, if not reconnect / relabel as required,

Is the lower heater controlled by a switch labelled OFF Peak (preferably the lower switch to avoid confusion) which is supplied from the OFF peak section of the Consumer unit, currently missing an MCB to be able to do that, if not reconnect / relabel as required,

 

[brianmoooore]

Have we established whether there is a Horstmann E7 style water heating controller in the property?
The most worrying aspect of this is that four electricians have already visited and failed to sort what appears to be a fairly simple problem for anyone worthy of that title.

 

[MeganS]

Not in my opinion!
I'm thinking what you call a knob is the cover of each immersion heater, which has the thermostat adjusting knob in it.

The bottom immersion is there to heat the whole tank, and that is the one normally powered by off-peak.
The upper immersion is for a "boost" if you run out of hot, normally fed from on-peak.
Does the light on the on-peak switch actually stay on all the time?

My first thought is that they are wired the wrong way round, but at this time of night I could be wrong. No doubt someone will be along to comment!

Yes sorry the black cap is what I am referring to (thermostat underneath I believe)

The photo I took was at 10am yesterday which would mean the light should be off - but yes light stays on always. Attached another photo which was taken just now at 10:25.
When we turn it off we are left without hot water which sparks my concern that it’s all wired incorrectly (or is it as simple as labelled?)

 

[MeganS]

So far it appears:

• the 'off-peak' section of the consumer unit seems to be fed from a DNO/Eon contactor, so should actually be 'off-peak'!
• (anybody care to comment on the presumably timed neutral feed to the contactor from meter, what's the other to the Henley?)
• the right hand 'off-peak' MCB position labelled 'immersion' has had the breaker removed
• so we don't know where power for the immersion heaters is now coming from.
• the bottom immersion heater works, but seems to need a new thermostat
• the top immersion heater does not work, but we don't know if it's lack of power, fuse, thermal cutout or faulty element etc.
• the flex to each of the immersion heaters seems to be transposed compared with what you would expect.
• the 3 x 500W Dinplex (presumably panel, not storage) heaters in the hallway are powered from peak rate electricity, which may be correct for that type of heater,

You would think it would be relatively straightforward for a competent electrician to sort this out !

Majority of bullet points are a little tricky for me to understand but thank you, will keep these all noted.

Just a point re your last point as I struggle to understand this too re the panel heaters and you are correct they are panel not storage.
So each of these (hallway, room 1 and room 2) have their own switch - shouldn’t be connected to on peak or off peak at all. When I do my maths to work out the costs (wattage x hours on x day rate/night rate) let’s take the highest day rate for example:
0.5KW x 5 hours x 0.44p kw/h = £1.1 so it should be costing me approx £1.10p to run these for 5 hours a day however when I pop these on and watch my ‘smart meter’ (the little screen thing I have plugged in at home) it drinks pounds for fun… and uses far more than £1.10p
I was under the impression these would not run off the on peak / off peak and just simply on day rate / night rate

 

[MeganS]

Have we established whether there is a Horstmann E7 style water heating controller in the property?
The most worrying aspect of this is that four electricians have already visited and failed to sort what appears to be a fairly simple problem for anyone worthy of that title.

Hi Brian
No I do not have this inside / or outside my home.
Thank you

 

[timhoward]

I'm also shocked that 4 electricians haven't been able to play a fairly simply game of "I wonder what is supplying this" and make a little progress.

@MeganS I'll try and repeat what others have said in simple terms. As far as I can tell the original design was that the very right hand bit of your consumer unit is designed to be powered only during off-peak times.
So it looks as though the original design was for the storage heaters and the lower immersion to be powered at night.
The upper immersion was probably intended for obtaining extra hot water and likely was intended to be manually switched on and off as required.

(to complicate matters some modern storage heaters can also be wired to also be used during the day, but ignore that for now)

The primary goal for any electrician (as said above in various ways) is identifying how the off-peak supply to the lower immersion was intended to work when originally installed.
I'm 99% sure there is a cable from the consumer unit to one of the two marked switches.
I'm also fairly sure that it isn't now connected to where it was once connected, as the breaker is missing.

I could speculate that if the lower immersion became faulty, someone could have decided the fault was it wasn't getting power (mis-diagnosis if they checked during the day) and decided to give it power from somewhere else.

But any electrician is simply looking to find the cable that was originally connected to the very right hand space on your consumer unit, check which switch it goes to, and check that in turn is connected to the lower one.
They would need to re-fit the missing circuit breaker (MCB) too.

Once that is done, we get into secondary issues, like does the immersion heater and it's stat work, and how is the on-peak unit powered. But at least the on-peak could then be turned off to immediately save you some money.

If you don't mind, post whereabouts in Essex you are (roughly). You've been messed around so much that someone might offer to help, as the diagnosis should be a quick job.

 

[brianmoooore]

If there's no E7 or similar, then there should be a feed for the immersion heaters from the off peak section of the CU.
I'm beginning to wonder whether there was a fault on the off peak feed (missing MCB), and a simple work around, to get a full cylinder of hot water back, was to swap the bottom immersion to the non off peak switch in the airing cupboard.
A competent electrician should be able to work out what the problem is, but not necessarily fix it, within half an hour

Edit: Looks like timhoward and I have come to the same conclusion at the same time!

 

[marconi]

My earlier post was too cryptic. If you do not live far from the Dartford Crossing, which is 10 minutes away from me in Essex/Havering, then I will pop round and have a look at what's what and take some photos for the fine folk who have posted so far to examine. And I will give you my 'tuppeny worth' too. I will not do the remedial work but I will visit for free as long as you are within 30 minutes of the DC. It will get me out of the house. Being married to my dear wife for 35 years means responding to a damsel in distress is a speciality of mine Daytime please.

 

[littlespark]

My earlier post was too cryptic. If you do not live far from the Dartford Crossing, which is 10 minutes away from me in Essex/Havering, then I will pop round and have a look at what's what and take some photos for the fine folk who have posted so far to examine. And I will give you my 'tuppeny worth' too. I will not do the remedial work but I will visit for free as long as you are within 30 minutes of the DC. It will get me out of the house. Daytime please.

You didn't say how many sugars you want in your tea....

OP, you should take up this offer. Then you will be in a better position to inform your local electricians what the problem actually is.

And, it will convince you never to use any of those electricians that have visited already, if they cant figure out the problem.

 

[James]

@marconi
is one of the few people who actually understands electricity and how it works, If you have the opportunity to serve him a cup of tea, your endeavours will not be wasted.

 

[MeganS]

My earlier post was too cryptic. If you do not live far from the Dartford Crossing, which is 10 minutes away from me in Essex/Havering, then I will pop round and have a look at what's what and take some photos for the fine folk who have posted so far to examine. And I will give you my 'tuppeny worth' too. I will not do the remedial work but I will visit for free as long as you are within 30 minutes of the DC. It will get me out of the house. Being married to my dear wife for 35 years means responding to a damsel in distress is a speciality of mine Daytime please.

Apologies I missed replying to the message within the many lovely explanations from all the others.
I have sent you a private message with further details
Thanks so much

 

[baldelectrician]

My ex apprentice (now an excellent qualified spark) now lives in London and has his own company

Once Marconi has been I can send him a message.
I don't know if he is doing domestic work or not but I can check

 

[MeganS]

My ex apprentice (now an excellent qualified spark) now lives in London and has his own company

Once Marconi has been I can send him a message.
I don't know if he is doing domestic work or not but I can check

That’s very kind, thank you
I am catching up with Marconi via phone call tomorrow so we’ll update you all as soon as he’s had a look

 

[marconi]

First Megan and her baby were very pleased with the generous help and advice from those who responded . I visited today and took a few photos and found out a few things:

1. There is a time switched off peak supply controlled by the meter and connected to the far right off peak main switch of the CU. I saw this supply turn on during my visit. The first picture below shows the peak and off peak supplies to two FCUs for the one and only storage heater.

2. Both immersion elements are sound as are their thermostats. However neither thermostat is a safety 'stat. Both were set to 55C. I have recommended the rod 'stats are changed to safety stats. The elements are both 11 inch. Each elements draws 13A. The switches for the elements are wrongly labelled. The top one labelled off peak feeds the upper elements and the lower one labelled on peak feeds the lower element. But see a later comment at 5 below.

3. The 24 hour supply for the storage heater is fed from the flat FRC. The off peak supply is from the first rcbo (B20A) to the right of the off peak main switch.

4. All the wall dimplex heaters are fed from the flat FRC and thus from the peak supply side of the board.

5. The two immersion heater switches are connected to the same peak supply B20A mcb - the one above which you see my ampclamp. I confirmed this by turning both 'stats to maximum and my amp clamp measured 26A and mcb buzzed.

6. The 13A socket for the water pressure pump is spurred off the immersion heater switch above it - you can see the wago connections behind the switch above the socket. Whereas the flat us wired in old colours the paralleling of the immersion heater switches and socket is done in new colours. The supply to all three from the board is the original old colours.

7. The second right B20A rcbo on the off peak supply says it is a for heater on the outside of the board bit is marked up with 'Imm' inside. I don't have a picture for that. There is an old colour cable connected to it but I could not establish where its goes. I suspect it is terminated in connectors behind the lower immersion heater switch or the 13 shower pump socket but I could not see if this was the case. I did not look behind the surface mounted 13 A socket - all a bit too awkward for me to do. Disconnecting this cable run, it measures open circuit between L-N.

8. I did not check how the lounge storage heater programmer was set up.

In brief then the only Eon controlled off peak heater is the storage heater in the lounge. Whether water heating uses off peak is by chance because Megan did not know that the whole flat (ie all the peak side loads) uses the lower tariff when it switches. (She has E10 which I checked on her bill). A phone call to be made to determine the off peak time slots but I have passed what I think they maybe and how to detect when off peak is available - the lounge right FCU neon light. The shower is fine albeit the flow rate is low which means that on the highest power setting the water temperature is too hot to bear. On the low power setting the water temperature is fine for a bloke but perhaps not hot enough for a damsel ;-). On the cold setting the water is cold and there is only a cold water supply to the shower.

The major work it seems to me is to provide peak and off peak supplies to the two IH elements, swap the stats to safety ones and provide a dedicated FRC supply perhaps for the shower pump 13A socket - or fit an fcu spurred peak IH switch.

I have to sign off now as wife home from hospital.

PS: I left the board with some postits on it but forgot to take a photo.

 

[littlespark]

But the question remains....

How many sugars?