Electric Heating/Hot Water Conundrum

QrizB

littleteapot said:

I'd be more concerned about that ancient little black box to the top right with the bell wire and T+E going to it than the ancient CU and slightly confusing metering setup. No idea what it actually does but I can't read the writing on it and it's an odd arrangement to have in a meter/CU cupboard.

It has a curly GEC logo. I can't make out the details but agree with @lohr500 that it looks a lot like a bell transformer. One of these (photo borrowed from eBay):

They're quite common in unmodernised CU cupboards.

littleteapot said:

My biggest concern would be whether it is connected to a suitably rated protective device to prevent the wires smoking or glowing red hot if a short circuit were to occur

I don't think they're a common problem, but if the bell is disused the transformer should probably be removed.

lohr500 said:

What puzzles me though is how the right hand meter receives any signal to energise the off peak rate. The meter model is a 5246B which according to the specification has no built in Economy 10 time switch or radio switch.

The meter claims to be a 5246C, which I think does have an internal clock?

Here's a zoom in from the OP's photo:

Scot_39

That white digital meter is a an Ampy 5246C - and I would hazard a guess it's pretty much - the pre rebadged to new ownership forerunner of this one - as looks to have the same format - and even the same 100A active led(*).

https://www.landisgyr.com/webfoo/wp-content/uploads/product-files/5246_Technical_Specification11.pdf

(Landis Gyr is branding name of outfit that took over Ampy)

 

And it appears in many forum posts on a quick google as that can be configured (digital meters like smart - just set to appropriate times) either an E7 or an E10 meter.

And as @QrizB above - it appears it could well be a 5 port dual rate meter in it's own right.

It is difficult from the pic - that meter change label is just "right in the wrong" position.

I may have been sold a dummy by the remaining black meter on LHS - is it still functioning (*) ?

I followed on from the above logic - as it does look like the output of the black meter is still connected.

And so thought - how could that be - that it could be the old meter is actually the whole house meter excl immersion / HW boiler and NSH - and the Ampy is purely being used for the switched E10.

And my only guess was if someone had had to replace say a defunct RTS second meter or an old analogue timer and second flat rate meter with a new device - they could have fitted the meter - and only used to the switched output. 

It is curious if in fact that is a 5 port dual rate meter - as the meter swap tag certainly only looks to have made a note of one reading (the 19037)  at time of switch.  

It would be nice to know if that modern white meter has 4 or 5 porsts and if 5 port - how many meter tails on which terminals.  (The spec drawing above indicates they are all in line - on other meters - the 5 / time switched live is more in front of the standard live).

(If 1,2,3,5 - and 5 is time switched - in one respect is actually not good - as that means you have E10 only for the heating circuits and not for the whole house (so no boosting heat with plug ins at off peak rate etc).)

No idea what the black GEC box is - and cannot tell if that twin and earth related - but the white wiring - is pretty low current - so...

(*)  Reading other forum posts it appears that the top LED indicates when the 100A output is actually active - i.e. when off peak power is being supplied (even if not drawn) on the fifth output if configured.

Sold a dummy on 2 meter photo ?

(*) Ooops - perhaps need to scratch all of that - as just opened the image full scale in another tab - and we could have been sold a dummy on the 2 meter thing.

Thought the connections to black meter were just hidden by shadow or some such - but now not so convinced.

This is going to sound really strange question - but is that old black analogue meter even operational anymore ?

As there appears to be a definite lack of visible live from the fuse itself - I can see the grey - but there is a gap - maybe half an inch to an inch - at both ends on live - and potentially also neutral end at meter. Where think can see the red/brown back board - between it and the fuse / assumed position of meter input terminals (assuming the two shown are ouputs ) - where the new feed to the new meter comes from.

So begs the question is that old black analogue meter even connected anymore ?

And if not what are the two outputs connected to - if anything ?

Are the meter incoming feeds hidden behind that red / brown back board in some way if so ?  I would have expected to see tham all - but then it's been a long time since looked at an old meter of that generation ( the bit of grey that looks like may have been something to do with old live just seems to stop / if not point as if entering the board)

And that then explains perhaps why the white meter 1000 pules / kWh led is on - with the 100A off - because the new meter is also supplying the day circuit - and indicating it is doing so.

So now doubting what to say -

I guess it's too early to have had a bill - but did anyone explain to your mother how to read the meter singular or meters - the old owner or the deemed supplier ?

Does that black meter dial still swing round and the numbers wind on.

There is a potential that the whole house is live - and the NSH using a common contactor - or a series of timer switches - elsewhere.  As that too can be driven by a meter - and it connected as a 4 port.

We are I suspect going to need better photos of both those meter connections - swinging that label gently out of the way if possible to give a better idea.

And possibly that black GEC box too.

lohr500

A photo with the label out of the way would help to clarify the situation, but I still think the black meter is feeding the top set of breakers in the cupboard. It looks to have a live and neutral going into the black meter and then a live and neutral running off to the right and then up the right hand side of the cupboard.

If as suggested above, the white meter does have a time switch, then my money says it is ONLY being used for the timed "fifth" wire output leading to the white fuses.

As also suggested, a new photo showing the readings on both meters would help.

If the system is configured as above AND the black meter is being used to provide the PEAK readings, with the white meter being used for the OFF PEAK readings, then surely this means the OP's mother will be paying the PEAK rate price during the OFF PEAK period for anything connected to those circuits at the top of the cupboard.

@Callyb69. 

• When you get chance, please can you take another photo with the white label held out of the way.
• Please also make sure the photo shows the readings on the black and white meters.
• Please press the blue button on the white meter and take a photo of what is shown on the display after each press.
• Finally, AND ONLY IF YOU ARE comfortable in doing this, SWITCH OFF the white fuse box by using the large ON switch to the right of the cover which says "FUSES" on it, carefully remove the oblong cover with "FUSES" written on it and take a photo of whatever is behind the cover. DO NOT touch anything behind the cover, replace the cover as soon as you have taken the photo and ONLY THEN switch back on the fuse box. Don't carry out this final step if you have any doubts about accessing the fuses behind the front cover. With the ON switch switched to OFF nothing should be live behind the cover, but safety is paramount.

Then post whatever photos you have taken and we can carry on figuring out how it is configured !

At the end of all of this and getting back to your original question, if it was me, I would stick with the storage heaters and immersion heater for hot water.

A good and honest electrician should be able to test the storage heaters to make sure none of the heating elements have failed. If some elements have failed then it may be possible to get them replaced.

If new storage heaters are needed, then as suggested by others, look at the newer high heat retention versions. They are more expensive but apparently hold the heat for longer. (I don't have any experience of them, but other regular foremites speak highly of them. To work at their best though and with minimal intervention, they do need two electricity circuits. A permanent live and a timed live. I suspect the existing wiring won't be set up like this given the age of the wiring.

If the fuse boxes are going to be changed anyway (and possibly the meter arrangements once we get to the bottom of the configuration) then it might be a good time to look at getting the extra wiring put in place to support modern storage heaters. I understand that some of the modern types can be used on a single electrical feed, but they then rely on their own onboard timers to determine when the off peak rates start and stop. This means they need checking regularly to make sure the timings haven't drifted. Something that may not be ideal for an elderly relative to attend to.  

For the hot water, I would be looking at the size and insulation on the tank. A well insulated and correctly sized tank should hold heat for a long time. Once heated up from cold using off peak electricity and depending on how much hot water is used, there should still be hot water at the end of the day when the next off peak cycle kicks in. So the reheating cycle isn't starting from a full tank of cold water again. 

Callyb69

@lohr500 @QrizB
Thanks so much for taking the time in helping to fathom this out.

I'm heading round there tomorrow after work so will get the additional photos and put my rubber boots on to check those fuses! 🤣

There is a working doorbell at the property and I've definitely seen the black/silver meter spin around.
The meter readings taken by the previous occupants family on the day of completion were one from the black meter and one from the white meter, so I guess it's all functioning, whether it timing and functioning properly is another matter! No bills yet but wouldn't expect the first one to be high usage as not occupied yet.

The electrician is on holiday ATM, but I'll have a more in-depth discussion with him as to what he can and can't do and why.

It's difficult with being at work all day to talk to the trades and don't want my mum being a cash cow for unnecessary work and expense, hense why I originally told her to use the heating as in over her 1st winter and then change, but when she was being swayed into changing, it helped to post the question on here. I'm so glad that the replies have been a resounding DO NOT ditch the NSH for fancy but expensive rads, as just gives a greater range of opinions.

She's lucky that she doesn't have to move in immediately so it can all get sorted and safe and working properly before she does.

Thanks again, the help is appreciated.

Jonboy_1984

If the electrician continues to claim both circuits cannot be updated I would look to get quotes from different electricians myself, as there should be a couple of different consumer unit formats that would work and one or other should fit.

If the existing storage heaters are old it might also be worth checking the elements as they do die eventually but are around £9 and normally only need a screwdriver to replace. Do Google the model first as some contain asbestos in the internal bricks (generally safe when sealed inside the heater).

Callyb69

Here goes, electrical cupboard spam. Hope it covers everything you mentioned .. @lohr500

Original photo


White meter wiring



Fuses


Meter cycles through 6 elements but only shows the one usage figure.
It goes: Rate 1, T (whatever that is!), Time (which is incorrect as 1hr20 out, so need to contact supplier), Date (also appears to be incorrect 05/09/29, Jumbled display and then End.
The crystal display seemed to be a bit dodgy and got worse the more I cycled through it, so reckon it'll need to be replaced anyway.

Callyb69

Also, I can confirm that the small black box is definitely an ancient bell transformer.

QrizB

Thank you very much for the new photos, all is clear!

The white meter has no connection to its 4th terminal, which (I think) proves that it is only used for the cheap rate supply.

Don't be in too much of a hurry to report the incorrect clock. Depending which way the time is out, it might work to your advantage - if the clock is slow, you'll get cheap-rate electricity later in the morning, when you're awake.

(Unless anyone thinks otherwise?)

Scot_39

OK - I fall back to the original section of my post.

That red connection was really hard to see - even when zoomed in on the original picture.

Black meter connected - second meter only connected to terminal 1,2,3 and 5 - so only I assume if the spec matches above link - supplying E10 off peak circuits on it's switched output.

So in many respects your system - appears to be operating more akin to my old RTS Heatiwse system - than a standard modern single meter E7 - or in my case E10 installation.

Where my RTS meter essentially did the job of your white meter - supplying off-peak only to the HW And NSH cicrcuits (seperately) in my case.

And the other meter just fed the rest of the house and billed at a different rate.

Wheras now my live feed is billed at E10 off-peak rates for E10's 10 hours - and then E10 premium peak rates for the other 14 hours.  My E10 for HW and NSH on switched obviously then always at off-peak.

There is also the potential issue that with 2 meters - you may have 2 MPAN's on your bill - and 2 standing charges.

But if your standard meter being billed at a closer to flat normal rate than E10 peak - that may well be a price worth paying.

T is probably the total of all rate registers.

My meter does T be default, then have to cycle through R1 and R2 and then unused rates.

I cannot remember the last time I looked at my actual meter time.  I used a spread sheet / algebra to work out my day night splits from totals on IHD - the IHD displays GMT / BST as expected - the meter itself ?

 

Re 1:20 is that the right direction if the meter time on GMT - some meters do not switch - so maybe only c20 mins out.

Most digital timers are better - but a quick google suggests in theory some could err +/- 1 second per day - 15-30 sec per month - so 3-6mins per year - and the meter is now 13 years old - either is possible - but 20mins seems more likely.

It's one of the benefits of in theory soon to be defunct RTS signal based meters - they can time sync to radio signal to fix any drift.

lohr500

Thanks Callyb69. The photos make it much clearer.

As per QrizB and Scot_39 comments and my suspicions, the black meter is providing a 24 hour supply to the house. The white meter is purely being used for off peak supply to whatever is connected to that white fuse box. (Hopefully the storage heaters and immersion heater). The little black box is the bell transformer, also as I suspected.

Lets try to untangle matters further :

In your 1st post you mentioned you were on an Economy 10 tariff. Do you know this for sure and do you know what the unit costs are for the peak and off peak rates? Also do you know in which geographic electricity area the house is located and which supplier are you with?

Are you able to contact the electricity supply company to ask if you are paying a single standing charge or two? They should also be able to tell you the region if you don't know.

If you are on a regular Economy 10 tariff, then the way the meters have been set up means your mother will be paying peak rate all the time for any electricity used on those circuits connected to the top fuse box. During the off peak period on Economy 7 or Economy 10, ALL the electricity should be metered at the off peak rate. So straight away there is good reason to get the meters sorted out.

Please can you try to get answers to the points above in italics, then we can dig deeper!!!

Good luck!!