Hi @richard777 , the type of set up you describe is generally what is used for an economy 7 tariff with the meter switching the second circuit on overnight - indeed without this, the storage heaters are likely to be rather expensive to use. 
Having said that, the two circuits are just that .. two individual circuits which could be operated from a single supply but there would need to be some changes to the internal wiring to make this work - and presumably some timing element if the meter isn’t going to make that happen. 
A supplier wouldn’t make internal changes but an electrician could and a time switch is simple to add if needed

Hi BPLighting, Yes, there had obviously been some intention to use Economy 7 when the flat was built 10 years ago.  However, it has never used an E7 tariff as far as I know and certainly didn’t do so before they put in a smart meter.   So really it was a bit of a scam on him, he doesn’t want E7 (doesn’t suit his lifestyle) but now he either has to get an electrician in to modify his wiring or do without the night storage heaters.  I wonder if we could sue Ovo for this.

The engineer is likely to have installed a meter that’s quite capable of feeding two circuits, one always live and the other live only during offpeak periods. If you could persuade him to share a photo of the meter, showing the cables to and from it (usually all at the bottom), we’d be able to tell what could be done. The chances are that it would only need a simple adjustment to the meter, done remotely by OVO.

If he uses the night storage heaters, then an Economy 7 tariff would probably be right for him, but it depends a lot on his usage pattern. The plan he’s on shouldn’t have any effect on how he uses electricity, but it does affect how much he pays for it.

As Firedog mentions, a photo could point to a potential solution. 
There is a way that a meter designed for peak and off peak circuits (traditionally what 2 separate circuits entails), can use both circuits but the energy is charged at the same ‘standard’ rate. I wonder if that was the idea here

@richard777 I’m wondering why your son “... �does] not have an Eco 7 tariff and doesn’t want one”  when “The install failed to supply the night heaters ...”. I can think of some reasons why this might be the case, e.g. there is other heavy usage going on at peak times which if charged at the E7 tariff’s day rate would eat up any savings made by charging the heaters at the lower night rate. It’s not unusual to see this during the summer, and for some customers during the rest of the year as well.

I had a look to see how the tariffs compare in my own region. They vary considerably around the country, so these figures are ‘for illustration only’:

The middle tariff here shows how a multi-rate meter can be set up to work like a standard one simply by setting the day and night rates to the same value. If you’re at all mathematically-minded, you can work out the threshold below which E7 wouldn’t pay, comparing offpeak usage to the total: A discussion: To stay on Economy 7 or not | The OVO Forum. Using this for the example above, 

• (29.93 - 26.68)/(29.93 - 20.18) = 33%

So if night-time consumption over the year is less than 33% of the total, E7 is probably not worth it.  

Trying to answer some of the questions.  I am getting my son to take another pic - I lost mine.

The meter was an Aclara and was obviously designed for 2 circuits as all the cables were plugged into it.  The engineer that installed it in 2022 didn’t check what was working.  A further one has just been and got the supply to the night heaters to work and did finally agree there was no fault in my son’s flat’s wiring.  He seemed to be unable to leave both circuits working and said he’d have to go Eco 7 to get that.

My son doesn’t want Eco 7 as he works during the day and would generally rather turn a heater on when he needs it.  If they make him have E7 he will pay more for this and his only advantage is that he’ll be able to heat up his night storage heater cheaply during the night which will release their heat when he’s not there and be cold by the evening when he’s back home.  He wants both circuits working because they are supposed to do so and did before they installed a smart meter.

That sounds useful @richard777 (partially) and the photo would just confirm what we're thinking about. @Emmanuelle_OVO is the tariff which offers the same rate on both feeds a specific one? Surely it’s possible to get this done?

@Firedog , yours is like that from what I remember .. 2 feeds, same tariff price on both?

First, no-one can ‘make him have E7’. That would be his choice entirely.

As regards turning on a heater when he needs it, storage heaters aren’t very good for this. Most modern types consist of a load of heat-retaining bricks in an insulating shroud. When their heating elements are switched on, they heat up the bricks without releasing much heat into the room because of the insulation. Then, once they’re hot, a fan blows cold room air over them and out to the room on demand, delivering nice warm air. If the fan is turned on at the same time as the heating element, the bricks won’t heat up as much and the whole thing will work like a sorry fan heater pushing some proportion of the heat being generated out into the room while the rest is warming up bricks, which will cool down overnight without making much difference to the room temperature. 

These heaters are most probably hard-wired into the dedicated circuit (i.e.no plug and socket for the heating element), so he may not be able to connect other real-time heaters (e.g. radiators or convectors) into that circuit anyway, whether there’s power to it or not.

I’m sorry if this isn’t making sense if your son’s set-up is radically different from mine. I don’t use my storage heaters for the same reason as his, so my E7 meter is configured with both night and day rates the same - the middle tariff of the three shown in my earlier screenshot. It’s a very different situation today from when I first got a smart meter some years ago; the night rate then was about 5p/unit compared with 20p today. The main heater alone used 10 units/day, so about £16 a month then, about £64 now. 

The promised photo might clear some things up.

Thank you all for your help and advice.  I’ll get my son to take another pic as agreed but he’s busy today.  I think Firedog’s suggestion of an E7 tariff with a single rate for both circuits is probably going to be the easy solution to this.  My son told me the E7 non-cheap rate is 5% higher than his current rate but if the flat, single rate is the same then that is a perfectly satisfactory answer.

Hey @richard777,

Your son can absolutely get a single rate tariff so he is charged the same for both registers. This topic might be helpful:

Economy 7 to Single Rate 

Although we're unable to physically change the functionality of meters right now. We can offer an Economy 7 to Single Rate plan! This means you’ll be paying the same rate for each register.

If this is something you’re interested in, please get in touch with our Support Team.