Storage heaters charging at peak rates with new smart meter?

I have to admit that I have never come across one of those before.

In this case then if the CU’s were set up as one for peak and one for off-peak that could explain why there is a ‘Water heater’ in both, one for each immersion unit.. (and for some reason called ‘water heater’ in one but ‘Pulsa’ in the other).

I guess that we need ​@david.sinc100 to confirm if there is one of those Pulsacoil water heaters?

If it is indeed ‘heat store’ as I suspected, then that is bound to be a real glutton for energy. For it to work effectively, the water in store must presumably be kept at a higher temperature than the 50-60º of an ordinary tank if the heat exchange mechanism is to work properly. It may well have been relatively economical with a 24-hour low-rate supply like that provided by THTC, but I could imagine it being ruinous if it has to operate at peak rate to work as intended. I see that some allegedly work with Economy 7-type tariffs, though.

I was hoping to be able to show a comparison, but the prices tables are apparently under construction in anticipation of tomorrow’s price-cap change. If my notes are accurate, the heating rate under THTC was 22.42 p/kWh, while the peak rate under Domestic economy is 28.40 p/kWh. 6 p/kWh would soon mount up if the thing is running during the day.

There should be a seperate ‘boost’ switch for the on-peak immersion coil so that it isn’t active all the time.

However I’m wondering if the setup in this case is missing a timer, which will be needed now that the supply has been changed to E7?

Here’s some wiring diagrams for different tariff setups from the installation manual for the latest model, which all show a boost controller on the on-peak heater.
Click the image on this page for a pdf of the manual: http://www.gasapplianceguide.co.uk/gledhill_pulsacoil.htm

The second one says it would be applicable for E7, note that it has a seperate timeswitch.

However if there is one of these heat stores fitted then it may have originally been wired as the first diagram, and the meter itself should be doing the switching to mimic the old supply.
If the meter isn’t doing that switching then the off-peak coil would be heating 24/7.

Thanks so much to everyone for your input and advice on this, it's so helpful.  Sorry for the delay - I hadn't spotted some of the more recent replies and was waiting to visit again to get a bit more info. 

Things I can confirm: 

- There are some other 'on demand' heaters (a panel heater and an electric fire) but my mother in law hasn't been using them so they shouldn't be the issue. 

- I checked last night at 11.30pm and the meter changed to indicate something different (LC1 LC2) so I think the tariff itself is configured correctly. 

- There is a Pulsacoil hot water tank.  My very basic understanding is that this heats hot water in coils during the off peak period which then heats cold water on demand as it's used during the day.  There is a separate immersion control but again my mother in law never uses this when she's in the flat on her own; only every so often when visitors are staying (multiple showers etc).  I can't see any timer switch attached to the tank. 

My own theory is that the storage heaters are now using power during both the peak and off peak periods.  There doesn't seem to be any timer or programmer attached to the heaters.  I think previously they were just connected to a completely separate meter. 

This morning at 9.30am I turned the Input on the heaters down to zero and the display unit was showing usage of 130W; I then turned the Input on the two heaters up and usage immediately went to 5KW.  I don't think it's reasonable for her to have to adjust the settings at these set times, she never had to previously. 

The other issue is that the heaters themselves seem to be operating differently on the new meter.  Even with the Output set at zero they are putting out heat overnight and then they are running out of heat later afternoon/evening.  Almost as though they are not storing the heat in the same way.

Thanks again!

Thanks very much - that clears up a lot.

First thing to note: the load control (LC) indicator doesn’t tell you anything about the tariff*. It only shows whether the switched circuit is live or not. This is the circuit that should be powering the storage heaters’ charging mechanism (the ‘input’ side) and the main coil in the water heater. Since the heaters can take charge outside of offpeak hours - as your experiment shows - it looks like the wiring needs adjusting. That’s a job for an electrician.

You could test this: the breakers numbered 11-13 are switched by the red main switch numbered 7-8. Repeat the ‘screw up the input setting’ experiment on one of the heaters during peak hours and check it starts charging (the IHD records something over 1.5 kW). Then trip switch 7-8 in the CU. If the heater stops charging, it’s the feed to that switch that has to be moved. It looks as if it should be coming from the left-hand white Henley block on the distribution board (DB). Since the electrician won’t be there when the switched circuit is live, he may not have to cut the power while he works.   

He should conduct the same investigation on the water heater, to make sure its main coil is only live during offpeak hours. 

Once this is done, he can check whether the heaters are now wired properly: the meter has a Boost feature, which overrides the automatic timed (ALCS) switch to allow the ‘offpeak’ circuit to be energized for a while during offpeak hours. You may have to press the meter’s buttons in a specific order to find the function: it varies from meter to meter. On mine (exactly the same model), it’s repeated B until I see Credit mode, then repeated A until Start Boost appears. The screen gives instructions for starting a 15-minute boost. The heater should come on, but should go off again 15 minutes later. 

Phew 😰
  

*   The tariff is set separately (in the ‘TOU matrix’), but ideally the load control switch and the tariff should change from peak to offpeak and back again at the same times. You should be able to see the Active TOU rate on the meter’s button B menu - it should be 1 during peak hours and 2 when offpeak.

Thanks ​@Firedog   I'll have to read that a few times to digest it but so appreciate all of the time you are putting into explaining this.  Thank you!

Hey ​@david.sinc100 

Thanks for popping back with that update. Firedog has left some really helpful advice.

I’d recommend getting in touch with the Support Team so they can take a look into this directly. They’ll be able to check some details and run a few things remotely if required.

There’s a couple of other topics which may be helpful:

Keep us updated with how you get on.

Hi All,my Dimplex storage heaters and Quantum water tank charging during peak hours instead of off peak hours after replacing my RTS electricity meter to smart anyone know what’s causing this issue? Thank you for your help😊

There are a number of reasons why this sort of situation might arise, so we’d have to have a lot more information about it before being able to say what’s wrong and how to put it right.

• When did the meter exchange take place?
• Where are you? The first part of the postcode is usually enough.
• What tariff are you on ? If your online account has caught up, you can probably see its name, prices and timings on the Plan page. 
• Please post some photos of your meter:
  *  A close-up taken after touching a button to light up the screen, clear enough for the display and all the markings on the meter to be legible;
  *  A view of the whole backboard or cabinet so we can clearly see the cables to and from the meter and any other associated equipment.
• Which indicator lamps are flashing on the communications hub (the box on top of the meter), and how frequently? 
• What (precise) times are the heaters charging up? 

We’ve seen several cases where there’s a mismatch between the timetable for switching the meter between recording peak and offpeak usage and the separate timetable for turning power to the storage heating circuit on and off. Given good communication between the meter and OVO headquarters, this sort of fault can often be easily and quickly remedied by remote control. Let’s see what your basic problem is before jumping to conclusions.

Hey ​@ucho 123 

Sorry to hear about this, though I am glad Firedog has already stopped by with some helpful advice on this already.

They’ve asked some really helpful questions to get you heading in the right direction, if you could reply to those, we’ll be able to suggest the next best steps.

We do have some other similar topics on the Forum like the one below:

Let us know how you’re getting on here, and if you still need support with this.