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Rank 3
June 24, 2025
Solved

Moving from THTC to Economy 10. Will the new smart meter charge storage heaters during off-peak periods only?

  • June 24, 2025
  • 30 replies
  • 949 views

We live in the northeast of Scotland (Buckie). Our space heating is solely electric via Dimplex Quantum Series G storage heaters. We have the usual THTC three consumer units (RTS space & water heating at off-peak rate, 24 hour off-peak ancilliary heating controls, and peak rate general usage). Our meter cupboard looks like this:

Meter Cupboard (Existing)

I have contacted OVO on several occasions enquiring as to the type of meter which will be installed and seeking confirmation that it can, and will, be set to charge the storage heaters during the three off-peak periods only. To date I have not received an answer.

I am in my 80’s. My wife is disabled and has zero mobility. Therefore, we are at home almost 24/7. As a result, the cost of space heating is by far the greatest component of our electricity bill. Making sure that charging of the storage heaters does not stray into the peak periods is therefore imperative.

Any help with answers would be much appreciated.

Best answer by Lukepeniket_OVO

Updated on 11/12/25 by Ben_OVO

 

Hey all hope you are ok!

I hope my reply will suffice appropriately, anything that is currently off-peak and controlled by the RTS signal will still be off peak once a smart meter is installed. As above I can see that you are aware they’ll be E10 timings also. 

If I have missed something just reply to me and ill get back to you today =].

 

We’ve got some really helpful topics on the Forum about the RadioTeleSwitch shutdown, check them out below for more information:

 

30 replies

Abby_OVO
Community Manager
Community Manager
July 14, 2025

Hey ​@Lecky 

 

I hope you found Firedog’s advice and resource useful. We also have a helpful topic in our Forum Library, check it out below:

 

 

If you could share a photo of your In-Home Display, we’ll be able to point you directly to the correct manual, but you can find helpful topics for each on the In-Home Display Forum Library Section.

 

Hope this helps.

Currently Playing: She's Electric
LeckyAuthor
Rank 3
July 16, 2025

Hello ​@Firedog 

Thanks. I have the IHD3-PPMID-AAA IHD also. The packaging tells me it is a Model: CA100005 TYPE 1. Lots of digits and letters but no user guide.

Firedog
Super User
Super User
July 16, 2025

 

I have the IHD3-PPMID-AAA IHD also … but no user guide.
  

Until very recently, user guides were available from the Chameleon website, but they appear today to have been taken down. I don’t know whether this is permanent or not. OVO did produce their own guide, which will still be valid in most respects. 

Noel | I have no official status; I'm just a volunteer who comes here to help other customers. My gear: Aclara SGM 1416-B Electricity-only E7 meter; Chameleon IHD3-PPMID-AAA | It may look as if I know what I’m talking about, but don’t let that fool you. |
Abby_OVO
Community Manager
Community Manager
July 17, 2025

Hey ​@Lecky 

 

@Firedog has left a really helpful OVO article about the IHD you have, I hope that was helpful. We also have a topic guide on the Forum which includes a lot of useful information on troubleshooting the IHD if you’re having any issues;

 

 

I hope this helps.

Currently Playing: She's Electric
LeckyAuthor
Rank 3
July 18, 2025

I have become better aquainted with my Chameleon IHD, and have determined that the new smart meter to which it is linked is indeed pre-programmed to switch according to Economy 10 off-peak times. The tarrifs displayed are also correct. Hooray! 

As an aside, I have drawn diagrams showing the Economy 10 timings graphically. I find them easier to read than printed lists. I have laminated A5 prints which I keep near the energy guzzlers for quick reference. If of any use, help yourselves.

 

 

Firedog
Super User
Super User
July 18, 2025

Every home should have one! Sadly, though, these will only help E10 customers in the Scottish Hydro DNO area ID 17, GSP region _P (now served by SSEN), because E10 timings elsewhere are not the same. This overview is probably as accurate as any you’ll find: 

Here’s a guide to DNO and GSPareas:
 

 

Noel | I have no official status; I'm just a volunteer who comes here to help other customers. My gear: Aclara SGM 1416-B Electricity-only E7 meter; Chameleon IHD3-PPMID-AAA | It may look as if I know what I’m talking about, but don’t let that fool you. |
LeckyAuthor
Rank 3
July 18, 2025

Will happily construct diagrams for different timings if anyone thinks they would be helpful.

Abby_OVO
Community Manager
Community Manager
July 21, 2025

Hey ​@Lecky 

 

I think that diagram is super helpful! It’s a great visual of the timings! 

 

As Firedog mentioned, there are timing differences per area - but if I spot someone unsure in future of their timing changes, I might have to tag you as they could probably really benefit from that same visual representation. Thanks Lecky for popping that on the thread.😊

Currently Playing: She's Electric
Newcomer
July 24, 2025

You should cancel that as cost more just do standard tariff as cheaper heaps on smart meters but I live by myself so if family maybe different 

Ben_OVO
Community Manager
Community Manager
July 25, 2025

Morning ​@Christopher matthews and a warm welcome to the OVO Forum 😁.

 

It can be cheaper on a single rate plan for some properties, however many properties have electricity supplies / setups that are cheaper to be billed on a dual rate tariff. I’ve seen many instances of customers making a small saving on a dual rate plan even when they don’t have storage heaters etc. Generally, if a property has storage heaters or an immersion tank that comes on at night, a dual rate plan will be the best option. This is something our Support Team can calculate for you if you’ve got a dual rate meter.

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