Economy 7 and energy usage concerns in new flat

Scot_39

Thanks @WiserMiser

I didn't realise that off peak LED was just programmed time.

https://www.tlc-direct.co.uk/Technical/DataSheets/Horstmann/EL7_U.PDF

I read to much into the difference between programmed times and the "cheap period" you should program them inside.  As that implies the installer might only have set for a fraction of the period or periods. And added 2+2 together - as in simple systems like mine - the one main element is just connected to off peak restricted supply.  

(Actually I used to have a boost button - that operated one of the contactors on my old RTS switch / meter - for HW output only (separate from te ain NSH output) - haven't had or needed boost since on spit off peak E10 - as it is het 3x per day)

Sorry @Simelthwate

Simelthwate

Scot_39 said:

That looks like RTS  - so need a meter swap appointment

The meter the 5196D - is I suspect an even earlier version than the 5235 - that black box as labelled - is an RTS timeswitch.

The white box above it is a series of contactors - again likely driven by the RTS - to power the off peak circuits.

If your mum / sister doesn't already have a replacement meter fitting booked (the previous occupants - even - let alone your mum / sister - should have been contacted about an upgrade).  

So as soon as they - or you if authorised already - can you need to contact thier supplier - and check the status - that they are registered as having an RTS system - (and if needby - does your mum need to be on their PSR - for medical reasons - and if not already in place - book a replacement meter fitting.

(Try not to panic about what you might have read for the last few months - as Ofgem have now stated that the 30th June date - are just recently announced to the media - it's now a phased shutdown - not a hard cut off date - and others are getting appointments - weeks after the orginal Jun 30th date - in Aug in one relatives case - and that inside the plan in theory - one recent poster here was given Sep - hopefully theirs still within the planned dates)

I cannot find a 5196D manual - but the 5193D and the 5235D - are both external timer controlled - and I have seen one customer with a 5196D and an old eletromechanical clock on the Ovo forum - complaining about the times drifting.

Your Observations

Ill have another look at the other info on the bills - and times - but the rates you quoted as per the question above are before VAT - and one the split use segments figures seems to agree with the reworked calcs above.

I on a first read - think it looks like your meter and your off peak switching do not match.

Arguably the meter rates match the white label on that rts - or at least the start time of rate 2 at 00:29.

And the boost light doesn't agree with the meter rate and the RTS label.

(The label which I suspect is a funny way of saying 11:30 norminal to 06:30 nominal GMT default with the traditional +/-15 min preset if any value for anti demand spike / surge offset (a difference betwwen meters so that 100,000s of homes dont switch 10+kW of heating and hot water on simultaneously - and cause a grid dip / spike).

As I read the meter rate 1/2 indication flashes - they are switching BST 00:29 - 00:30 with 1/2 min offset and possibly then back maybe 07:29 DST - 07:30 possibly with a minute or so offset.

That was as expected from the label.

But the off peak supply appears to be switching completely differently 22:30 - actually outside the 10-9 GMT regional off peak window.  And does appear to be recording on rate 1 at peak rate - so defintely needs investigating.

Another Question from your timed observations

You did not say what rate - 1 or 2 - was flashing on meter at 0600 and 0731 observations (I would have hoped it might switch back at 07:30) - was that because it was still rate 2 and didnt switch back until closer to 10?

PS 1 Can you provide the model number - for that HW boost controller (I am assuming its some vairant on Horstman / Secure E7 series) - but cannot see an exact match ?

And if you can check the timing settings that get selected when you throw the switch from off to timed.

PS 2 E7 vs SR

Assuming niether of those registers has wrapped since install - the R2 may be close - that looks like a long term 60+% off peak ratio - so definitely in the E7 cheaper than SR camp.  

Thats an impressive dedication of times - and a severe lack of sleep - if all by one person. So pace yourself.

Hope things go OK at hospital.

Thank you very much for explaining all this and for your kind wishes about the hospital.

My mum was asked if she wanted to switch to a smart meter but she didn't want to and they said that was OK. No one told her that she needed to switch meter so maybe they don't know she has an RTS meter. I can see on her online account that they have appointments available to book this week/next week to install a smart meter but I will ask her to call them when I'm there next instead to make sure they know she's on RTS and check she's on the PRS (I believe she is). I have access to her online account but I don't have authority to speak to them myself.

Regarding the switching times and off-peak light, as you say things are not matching and there is defnitely something wrong with the off-peak timing of 22:30. I am finding it all totally confusing, on top of the day and night being the wrong way round on the bill. 

"You did not say what rate - 1 or 2 - was flashing on meter at 0600 and 0731 observations (I would have hoped it might switch back at 07:30) - was that because it was still rate 2 and didnt switch back until closer to 10?"
-- After 00:30 I did not go down to the meter room until 10:05 in the morning. I was only observing the off-peak light on the Horstmann panel so do not know what meter rates were flashing during this period. When I go back there I will need to check which rate is flashing just before and just after each of 0600 and 0730. 

I cannot see a model on the Horstmann hot water controller but I think it is this one: tlc-direct.co.uk/Technical/DataSheets/Horstmann/EL7_U.PDF.  When they moved in I couldn't see a way to change what time it comes on for normal usage. It looked like only the Boost timings could be changed so I thought that maybe it somehow 'knew' what off-peak times were either due to some signal from EOn or something to do with the off-peak circuit on the consumer unit becoming live. It was only last week that I realised the immersion was turning on outside off-peak times (and even with the peak water heater circuit switched off on the consumer unit)

Looking at the manual now, it says "Your Installer would have already set the off-peak heating time, however if you require extra hot water on a daily basis you can set one of the remaining programmable heating times". It looks like I can therefore adjust the timings using a recessed Set button. I will ask my sister if she can look at what times it is currently set for. If not it will have to wait until I am back there.

Indeed, I did have a lack of sleep that day. I had set some alarms to wake up and check at various points but other times I just happen to wake up so checked then too. I thought it was important to get to the bottom of it for my mum.

Simelthwate

Scot_39 said:

Flagging up the rate error - might produce a bill demanding the c20p difference for last n weeks on the unit difference - or to be fairer a proportion of it.  

It does need fixing - but then so does the RTS.  

The OP gained a bit on HW billed at correct 15p - on rate r1 after 22:30 in his observations, but may equally have lost some billed overnight at R2 at 35p etc.  Its virtually impossible to correct the error accurately - and fear EOn would look for max recovery - a simple swap (another often overlooked advantage of smart meters 1/2 hourly logging is can be calculated if need be)

So given the whole set-up appears at least part RTS - might be best to concentrate on getting a meter upgrade before winter - and then make sure EOn bill day at day and night at night on the new meter.

And if its a large block (given 12 it could be) the OP might want to ask EOn to provide a dual band or potentially wired Alt Han install to get a working IHD in flat as well

Wow, so the bill is meant to be even higher than it was. My mum already thought it was crazy expensive compared to dual fuel.

If we get EOn to fit a smart meter in the next week or so, including the necessary elements that allow for a working IHD as you suggest, do you think that will solve some of the syncing problems? If the RTS is out of the equation it seems like it might simplify things a bit.

Simelthwate

Ildhund said:

Simelthwate said:

MPAN
The Meter Time-Switch Code is 811
Region Code is 16

Bit late to the party - sorry!
MTC 811 is one of the original 1996 Economy 7 codes, supported as far as I can see by all distributors. Its description is "NHH 7hr E7 GMT Non-Prog T/S" and its associated SSC is 0151. This SSC translates to TPRs 00043 and 00210:

SSC	TPR	Description	Name
151	43	Weekdays & Weekends 0000-0030, 0730-2400	Day
151	210	All days 0030-0730	Off Peak

This is what NORWEB will be using to bill E.On Next for the electricity passing through this meter, so it's in their interests as well as the customer's to get this right. 

No need to apologise at all. Thank you for looking into this and confirming that the off-peak period is 0030-0730. Now I just need to make sure that the hot water and heating get aligned to this somehow.

WiserMiser

Just to recap, the little red lever on the black RTS unit is the authoritative source of truth.  Up and it's the daytime rate, down and it's night time.  The thin wire instructs the meter to set the appropriate rate.  The RTS and the meter should switch back and forth at exactly the same moments.  You can't change those times, on a basic E7 tariff it's virtually certain that they're set in stone and won't change from one night to the next (apart from possible GMT/BST changes, but that's largely history now).

The Horstmann unit is completely dumb.  It doesn't know which rate is in operation, it just tries to mimic them.  You have to check that its clock is correct, and you have to tell it when to liven up the supply to the lower immersion heater, assuming there are two.  You have to make sure that the whole time the circuit is live (top red light lit on the Horstmann) fits entirely within the timeslot(s) when the RTS lever is in the down position.

Regarding E.On Next, you need to get them to rebill at the correct rates, night being the cheap rate.  Unfortunately there's nothing you can do if the Horstmann was switching the immersion heater on at the wrong time, that's water under the bridge and sadly it's your problem not theirs.

However, you should ask for compo from E.On Next for the serious overcharging: it should never have been allowed to happen.  Ask for £100 politely but firmly, and consider accepting £50.  Or £150 and settle for £100 if you're bold !  Go to the Ombudsman if they don't play ball.

Unfortunately you'll have to check the times and re-program the Horstmann again after the meter has been changed because the new E7 times won't be exactly the same.  The only way to be sure will be to check the new meter's display, you mustn't rely on what you are told or read because it'll be an expensive mistake forever if you get it wrong.

Scot_39

As the post by @WiserMiser has pointed out - I think we were both mistakenly interpreting off peak LED as literally off peak from meter.

(The same way some posters here ask if the NSH or immersion spur has a LED on the switch to indicate wires live)

Turns out if download a wiring diagram for a similar switch - the whole HW system only takes power from live circuit - even have boost and main tank heater - which is fine if the timings match the tariff rates - but only also on standard single meter (possibly even only single element ?) installs.

(On my old RTS with twin meters - that would have meant always at day rate - as my off peak only applied to restricted back then) 

The whole thing makes more sense now - as there are two timers in the loop - the E7 water switch program driving the off peak light not the supply itself - heating water from a 24/7 live feed - and I hope the RTS driving the NSH supply and the meter rate.

So the main load hopefully still in sync - albeit at wrong rate.

As I fear that means NSH will be active at rate 2 times - and as the bills at 35p as per those bills.

Luckily its summer time - so hopefully minimal use of NSH for last n weeks.

Wonder if the previous occupants had always been paying the wrong rate - or whether - if your mum switched supplier from old to (maybe as Next Flex sounds vaguely like their standard SVT tariff name) EOnNext  - to generate the error (but maybe that would / should have caused a reading mismatch during switch process reading validation).

Now arguably - your mum is currently getting HW at correct rate - for the 22:30 - 23:xx HW timing - as rate 1 is still active and rate 1 is being charged at the 15.xp

However later in the morning like at somewhere between 2:31 am and 4:21 to 6am - when looks like the second block timing may be set - because rate 2 billed at 35p and is "probably" active - given RTS label and the MTC info above - both suggest a solid 7 hr block - she will be overpaying for the those c2 hrs - if triggers.  

With any luck and little use between the first set period and second  - it wouldn't draw much power at the 35p rate.

Ill leave it between you and your sister if you want to narrow down the rate timings - and if so - via the meter cabinet - or in home via a live wire connector - or listening for the NSH charging to save such trips - around c23:30 or c0730 c0830 would seem obvious test points..

Simelthwate

WiserMiser said:

It seems that your immersion heaters are not connected to a circuit that's switched by the meter: they use the Horstmann 7 timer (old version) instead.  That's a cheapo solution that can work well, but it's inherently risky.  The timer switches on the immersion heater when it thinks it's off-peak.  But be warned, if it hasn't been programmed correctly to your actual off-peak times (not what someone has told you they should be) or the clock isn't showing the correct time, your hot water will turn out to be super expensive.

Thanks. I understand. It certainly seems like it's not been programmed to match the off-peak times which is strange because the last owners were on the same tariff. I defnitely need to find out what times it's been programmed for. Hopefully my sister can check it tomorrow.  The clock is showing the following: On the Summer setting it matches the current time (e.g. 22:45) and the Winter setting shows 1 hour later (e.g 23:45). It is left on the Summer setting. Do the clock settings seem correct?

WiserMiser

Scot_39 said:

As the post by @WiserMiser has pointed out - I think we were both mistakenly interpreting off peak LED as literally off peak from meter.

(The same way some posters here ask if the NSH or immersion spur has a LED on the switch to indicate wires live)

It's always a good idea to have an easily visible indicator on a storage heater supply so that you know when the night rate is available and you can use high power appliances more cheaply.  It also allows any unexpected changes in the times to be spotted, very important if using local timers.

Scot_39 said:

I'll leave it between you and your sister if you want to narrow down the rate timings - and if so - via the meter cabinet - or in home via a live wire connector - or listening for the NSH charging to save such trips - around c23:30 or c0730 c0830 would seem obvious test points..

It's essential to know the exact switching times if you're using local timers like the Horstmann.  You can check over a few evenings if you don't want to keep staring at the meter.  Having established the exact start time, you can then check almost seven hours later.  If it switches back after exactly seven hours then it's 'job done'.  If not, it's probably a 'split shift' cheap rate, so it would need checking almost nine hours after the cheap rate starts.

The best solution is to feed the immersion heater and the NSHs from circuits switched by the meter, then heating up anything at peak rate will be impossible unless the boost button is used.  However, that does require wiring changes and potential redecoration, which is why some people settle for the 'cheap but fiddly and risky' local timer solution.

Simelthwate

WiserMiser said:

Have a look at the hot tank to confirm that there are two immersion heaters fitted.  There's usually one at the bottom which gives you a full tank that's heated overnight at the cheap E7 rate.  The one about halfway up should normally be left switched off (Horstmann white switch set to Off, Boost Selection slide switch set to Manual).  If you often run out of hot water during the day, make the start time a bit earlier.  If you occasionally run out of hot water during the day, press the Boost button to give half a tank of peak rate (= expensive) hot water.  The Boost button should be considered as being 'For Emergency Use Only', e.g. if you've had visitors taking full baths or long showers, or after returning from a holiday.

The water cylinder is in a cupboard in the bathroom.
There are two immersions fitted. There is also a separate thin wire coming out of a hole to the left of the top one:

The thin wire seems to go into the wall (see below photo), the other side of which is a tiled bathroom wall.
Each immersion is connected to a switch (see bottom left of photo):


On the Horstmann, the Boost is set to 'Manual Boost' but we never press the Boost button. Would it be a good idea to turn off the power switch that's connected to the top immersion if we don't use the Boost? Or is there no need as long as it's set to Manual Boost on the controller?

Simelthwate

WiserMiser said:

Just to recap, the little red lever on the black RTS unit is the authoritative source of truth.  Up and it's the daytime rate, down and it's night time.  The thin wire instructs the meter to set the appropriate rate.  The RTS and the meter should switch back and forth at exactly the same moments.  You can't change those times, on a basic E7 tariff it's virtually certain that they're set in stone and won't change from one night to the next (apart from possible GMT/BST changes, but that's largely history now).

The Horstmann unit is completely dumb.  It doesn't know which rate is in operation, it just tries to mimic them.  You have to check that its clock is correct, and you have to tell it when to liven up the supply to the lower immersion heater, assuming there are two.  You have to make sure that the whole time the circuit is live (top red light lit on the Horstmann) fits entirely within the timeslot(s) when the RTS lever is in the down position.

Thanks for your expertise. It's good to know what the ultimate source of truth is. My sister probably won't be able to stay up late/get up early to check when the red lever switches so I will need to do it. Looks like I won't be back there until next week now unfortunately. However, she should be able to check the Horstmann programming tomorrow so at least know when it is coming on.

What I don't understand is where the 'Water Heater Day' and 'Water Heater Off Peak' circuits on the conusmer unit come into it.

Although it's On in the photo, I switched the 'Water Heater Day' circuit to Off position a few days ago. With only the 'Water Heater Off Peak' circuit in On position, the water heater still comes on at peak times. How come? What determines when these circuits are active and in what way do they affect when the immersion heater comes on? Is it the programmed Horstmann times that determine when the Day and Off-peak circuits are live?  

What about the storage heaters? What determines when they come on? Each one has a switch on the wall next to it and they are all currently switched off there. We have never turned these switches on so don't know if or when they would come on if we wanted to use the heating.