Complex Multi-Rate Meter & Heating types

  • 27 September 2023
  • 49 replies
Complex Multi-Rate Meter & Heating types
Userlevel 7

Updated on 24/10/23 by Emmanuelle_OVO


The Radio Teleswich System shutdown is now due April 2024

Multi-rate meters are also sometimes known as ‘complex’ or ‘exotic’ meters


These older types of meter are being phased out and support for them will be ending soon. If you have one of these meters, and think you’ll be affected, don’t worry- we’ll be in touch to arrange an upgrade to make sure your heating and hot water keeps working properly.


So, what is an ‘exotic meter type’ and why is support for some of these meters ending? Let’s find out more...


We’re saying goodbye to Radio Teleswitch Meters (RTS Meter) and Dynamically Teleswitched Meters (DTS Meter).


Support is ending for old electric meters that use Radio Teleswitches. The Radio Teleswitch System (or RTS) was created to help with electricity meters that had special tariffs (such as Economy 7) before smart meters came along. 


Even though it has a few features that are seen in today’s smart meters, such as automatically turning heating or hot water on or off, it isn’t quite as smart. It can’t send us your meter readings remotely to make sure your bills are correct.


RTS Meters (sometimes known as Dynamically Teleswitched Meters), are old meter types. A Radio Teleswitch device would also be installed, alongside the electricity meter, to pick up the RTS signals and control the time switching features on the meter.


The shutdown of the RTS service would mean that the teleswitching features, to allow electricity meters to be switched between tariff rates and to allow the switching of electrical loads such as heaters, would completely stop working. 


Older meter types aren’t being installed by suppliers anymore, and many of these meters are reaching their end (certifications). 


Here are some of the RTS/DTS tariffs:


  • Economy 7*
  • Economy 10*
  • Total Heat Total Control
  • Weathercall
  • HeatWise
  • WarmWise
  • Storage Heat Control
  • White Meter
  • Superdeal
  • Flexiheat
  • Comfort Plus
  • Comfort Plus Control
  • Twin Heat


*Economy 7 or 10 meters with controlled load. Controlled load is a special type of electricity rate, or tariff, for high-energy appliances. It's ideal for things that use a lot of energy, like underfloor heating or hot water systems.*


Want to find out more about this topic? Why not check out this helpful FAQ:


Don’t forget- If you have a meter that’s affected, we’ll be in touch to arrange a meter and tariff upgrade to keep your heating and hot water working.


Exotic Tariffs 


Storage heating control (SHC)


With Storage Heating Control you usually have two separate meters. One meter records energy used during the off-peak periods, and the other records all other electricity used.


Customers save the most if they have storage heating and hot water. These heat up during the off-peak times, on the cheaper rate, to last throughout the day. 


The standard meter records all the domestic usage (cooking, lights, electronic devices) in a home. There are no off-peak times for any domestic use, and these appliances can be used at any time. 


What about heating and hot water?


SHC was designed to work with storage heaters. To benefit from the off-peak price, the storage heating and hot water would need to be connected to the off-peak meter. If you have this type of meter and are unsure if yours is connected, an electrician can check this for you.


Out of off-peak times, any appliances connected to the off-peak meter won’t operate, so SHC isn’t suitable for direct acting heating, such as a towel rail or underfloor heating. 


As long as the storage heaters are connected to the off-peak meter, they’ll come on automatically during off-peak periods. 


SHC offers 8 hours per day for customers to charge their storage heaters and heat their hot water. At least 3 of these hours will be available from between 10pm and 10am. There’s also a minimum of 2 hours between 10am and 10pm.


The times do vary which means we can’t give a customer the exact times their off-peak will operate. But, as long as the heating and hot water is connected to the off-peak meter, they should automatically come on when the cheaper rate is available. 


SHC doesn’t offer a cheaper rate for domestic appliances, which means regardless of the time these appliances are being used, they’ll always be charged at the standard rate. 


Dimplex Quantum storage heaters work in the same way as standard night storage heaters, by charging up during off-peak times at a cheaper rate. Quantum heaters have thermostats and a digital programmer, which means that operating them is much more ‘hands-free’.


You can choose the times of the day when the heat can be released, and you can also choose the temperature. The heater automatically works out how much to charge overnight. A fan helps to draw air through the heater and warm up the room when the thermostat senses that the temperature has dropped.

Quantum heaters are better insulated than older models, meaning that less heat escapes when it isn’t needed. This is better for both your wallet and the planet. 


Input/Output Dial Storage Heaters work by storing heat made by cheap off-peak electricity and releasing it during the day.

An input setting allows customers to control the amount of heat that the heater stores during off-peak hours. The higher the setting the more heat is stored, but this also means running costs will be higher.

An output setting allows a customer to control the amount of heat that the storage heater releases. The higher the setting, the quicker the heat is released into the room. The recommendation is to keep the output setting low when heat isn’t needed (like in the night or when the home is empty).

Total Heating Total Control (THTC)


How many meters? 

THTC is usually a two meter set up. Although pay as you go THTC meters normally only have one meter.


What does it do? 

With THTC you normally have two meters with one rate on each. One meter records all of the domestic usage at the property (lights, sockets etc) and the other records the usage from the heating and hot water in the home. 


On the heating control meter there is the stored circuit which gives a customer between 5 & 12 hours daily based on the weather forecast to store heat, and around 5 hours 45 minutes to heat water daily. Because the off peak times are determined in part by the weather forecast we are unable to tell a consumer exactly when the peak/off peak hours are. 


There is also the 24 hour off peak circuit, this is for any additional heating and hot water in the home, panel heaters, focal point fires, electric towel rails, electric showers, and to boost hot water. 


What about heating and hot water?

THTC was designed to work with storage heaters, and they should charge automatically during the off peak hours, along with the hot water. As long as any additional heating appliances are connected to the 24 hour circuit, they will be charged at the lower rate regardless of what time they are being used. This is not something we are able to check for a customer, they would need a private electrician to tell them what is wired where. 


To find out more about THTC and SHC please check out our helpful guide on the website.




Superdeal is usually a one meter set up. It is only available in the Meter Point Administration Number (MPAN) 20 area. 


Unsure what your MPAN number is or who your Distribution Network Operator is? Check out our handy Tutorial below:



What does it do? 

With Superdeal you get one meter which has three rates of electricity; Day rate, Night rate,  and Off-peak rate. The Day rate records energy used between 7am and midnight, the night records domestic (lights, electrical appliances, sockets) energy between midnight and 7am, the stored records for 5 hours overnight and has a 2 hour afternoon boost. 


Superdeal provides 7 hours of off peak electricity over 2 periods  for heating and hot water appliances. It provides a 7 hour off peak period overnight for all domestic appliances. 


What about heating and hot water?

Superdeal was designed to work with storage heating, a customer receives 5 hours of charge over night for their storage heaters and hot water, and an additional 2 hours afternoon boost. During these 7 hours, the heating and hot water should automatically come on.


This meter is handy for customers who need to top up their heat during the day so they have enough for the evening, if they have older heaters or if they are at home and use their stored heat frequently throughout the day. 




  • Flexiheat is designed to work with electric storage heating
  • The tariff offers 7 hours of cheaper, off-peak electricity for stored heat 
  • Energy used outside of the off-peak times costs more at the standard rate, so if you have this set up we’d encourage you to use more during the cheaper times
  • Usually not suitable for homes with Gas or Oil heating 


How does it work?


With Flexiheat you get one meter which has three rates. One rate records all the electricity you use during the day, another records all of the electricity you use during the evening and weekend period, and the third measures all the electricity you use during the 7 hours of stored heat. 


Flexiheat works by storing up heat and hot water using the lowest possible rate of electricity.


All the electricity you use during the off-peak times is charged at the cheaper rate, not just your heating and hot water.


When are the cheaper off-peak times?


A consumer is supplied with 7 hours at the cheapest rate for stored heat. At least two of those hours will be during the day - which tops up heating and hot water.


They would also benefit from cheaper electricity for all domestic appliances used on weekdays between 7:30pm to 7.30am, and weekends from Friday 7.30pm to Monday 7.30am. In addition to this, Flexiheat customers benefit from cheaper electricity for all domestic appliances used between 24 December and 1st January.


There is more information about Flexiheat and Superdeal here.




Heatwise is designed to work with electric storage heating. It can be a 1 or 2 meter setup which is only found in MPAN 11. The meter(s) generally have a combined 3 or 4 rates and provide 10 hours of off peak electricity for hard wired heating and water appliances. It’s usually not suitable for homes with Gas or Oil heating


How does it work?


All the electricity used during the off-peak times is charged at the cheaper rate, not just heating and hot water. 


When are the cheaper off-peak times?


Afternoons Monday to Friday – 3 hours between 1pm and 4.30pm

Afternoons Saturday and Sunday – 3 hours between 1pm and 5.30pm


Evenings Monday to Sunday – 2 hours between 5.30pm and 10pm


Night’s Monday to Friday – 5 hours between midnight and 7am

Night’s Saturday and Sunday – 5 hours between midnight and 8am


Economy 10


Economy 10 provides 10 hours of off-peak electricity for everything in the home and can be suitable for a number of electric heating systems, including wet electric central heating and storage heaters. Storage heaters will automatically store at the off-peak times on the lower rate.


Electric immersion water heaters will also usually heat automatically during the off-peak hours and you may want to install an external timer to regulate when and for how long the water heats.  The off-peak hours offered with an Economy 10 plan add up to 10 hours during each 24-hour period – which is why this plan is known as Economy 10. 


(MPAN) 10,11,12, 14,15,16,19,20, 21, 22, 23

(Traditional, Pay as you go & Smart)

12.00am - 5.00am 1.00pm - 4.00pm 8.00pm - 10.00pm (GMT)

1.00am - 6.00am 2.00pm - 5.00pm 9.00pm - 11.00pm (BST)


18 & 13


4:30am - 7:30am 1:00pm - 4:00pm 8:30pm - 12:30am


(Paygo & Smart)

4:30am - 7:30am 1:00pm - 4:00pm 8:30pm - 12:30am (GMT)

5:30am - 8:30am 2:00pm - 5:00pm 9:30pm - 01:30am (BST)




4:30am - 7:30am 1:30pm - 4:30pm 8:30pm - 12:30am


(Pay as you go and Smart)

4:30am - 7:30am 1:30pm - 4:30pm 8:30pm - 12:30am (GMT)

5:30am - 8:30am 2:30pm - 5:30pm 9:30pm - 01:30am (BST)


49 replies

Userlevel 7

Hey Community Members! 


Does anyone have one of these Complex Meter Set ups? If so, fancy uploading a photo? This would be a really helpful addition to the FAQ 😊

Userlevel 7
Badge +1

Wikipedia has one or two you can use. They’re either Public Domain, CC0 or CC BY-SA so copyright isn’t too much of a problem either.



In the process of migration. With SSE we had 2 meters to service our Superdeal tariff & paid one standing charge. Because we have 2 meters OVO now want to charge us 2 standing charges adding £180 to our annual bill. Both meters are in the same location & property.

Userlevel 7

Amazing thanks Blastoise!!!!

Userlevel 7
Badge +1

Hi @johndebs ,

This is an edge case. Can you bear with me for a bit and I’ll get some advice on this one?

Thanks for hanging in there! I’ll be back ASAP.

No problem. We have for the past 25+ years with SSE had this 2 meter setup inherited from the previous house owners. One meter has 3 rates (day, night & stored heat for the water) & the single meter has one rate for the stored heat (storage heaters). I guess there is an ancient reason why the stored heat elements could not be wired to the one meter. I feel that with one electric supply despite 2 meters to service it, I should only pay for one standing charge! I cannot believe I am the only case like this. Less than a week in with OVO & they are already throwing me problems! Unimpressed!


Userlevel 7

Hey @johndebs,


I’ve just asked about this internally and was advised,


If a customer has two supplies that are related (ie. Related Meter Point Administration Number (MPAN) - which should be the case for a Superdeal customer) then they will receive the 1 standing charge. If they two supplies that are unrelated (separate MPANs) then they should be charged two standing charges. One for each supply. 


Do your meters share an MPAN supply number?

We have 3 supply numbers listed & 2 meters both of which run the Superdeal tariff. One meter giving day, night & stored heat (our water) & the 2nd gives one reading which is the stored heat (storage heaters).

Userlevel 7

If those 3 supply numbers are related due to the Superdeal tariff, you won’t be charged for multiple standing charges @johndebs. It’s tricky for us to advice much more as we can’t access your account to view how those MPANS are listed on our system or the national database. If you called our Support team using the number registered on your account, you’ll get through to advisors trained in these meter types and tariffs who should be able to clarify: 0330 303 5063.



I migrated from SSE and have an economy 10 tariff which I’m happy with.  Is there any update on whether I can install a smart meter and keep my current economy 10 tariff/hours?  Economy 7 would not work for me 

Userlevel 7

It depends on where you live. I see that there is an Economy 10 plan ‘available for sale’ in Northern Scotland (I checked for Glasgow), so it’s not out of the question.

Visit Our prices | OVO Energy and put in your postcode. Apply all the filters to get a more intelligible listing; I used these:


The ‘Simpler Energy - Economy 10 - 01/10/2023’ plan was near the bottom of the ridiculously long list.

Despite all this, it’s not certain that you’ll be able to persuade OVO to accommodate you. I don’t know why it’s so difficult for some customers.

Thank you very much for this reply.  Just to add (as I was not very clear in my initial post), I already have an economy 10 meter and tariff which works fine with OVO having migrated from SSE.


im just unsure if I can upgrade to a smart meter as I’d hate to lose my 10 x off-peak hours.

Userlevel 7

Aaah, OK, sorry. 

We’ve seen plenty of problems with people moving with odd SSE tariffs to smart meters, but if you’re already on an OVO E10 plan, it ought to be problem-free to exchange the meter for a smart one. It seems to depend a lot on luck and the competence of the installing engineer as to whether it works seamlessly or not. Sorry not to be more helpful 🙄

Userlevel 7

Hi @kath5467,


Due to your economy 10 meter set up, it’s very likely that you’re part of a group of customers that have specialist trained agents available to speak to when you call. If you call us on the number linked to your OVO account (you can check this via your online account if you’re unsure), they will be able to hear some details about your set up and advise about a smart meter: 0330 303 5063. 


Let us know how it goes!

Hi Tim,

It says support for my type of old meter (Superdeal) is ending soon but when exactly? Will it mean a smart meter to be fitted? We have a vulnerable situation here & would not be able to suffer a winter switch off whilst a new meter is being fitted along with it’s possible complications.

Userlevel 7
Badge +2

Hi Tim,

It says support for my type of old meter (Superdeal) is ending soon but when exactly? Will it mean a smart meter to be fitted? We have a vulnerable situation here & would not be able to suffer a winter switch off whilst a new meter is being fitted along with it’s possible complications.

Hi @johndebs 

I don’t work for ovo, i am just a customer like you.

There is the latest information from OVO here

It is currrently due to end on 31st March 2024.

Have you signed up for the priority service register?


If you called the OVO Support team using the phone number registered on your account, you’ll get through to advisors trained in these meter types and tariffs who should be able to help 0330 303 5063.

Hi, I have economy 7 with night time storage heaters and hot water tank. I have asked for a smart meter to be able to callculate  usage but have been informed that a smart meter is not compatible. What will happen after March? I have been told to expect an email but I would like to know what will happen. Can I be forced on to a different tariff with only one meter reading and no off peak electricity?

Userlevel 7
Badge +1

Hi @Sylvia Murray ,

The best I can say in this case is that OVO would be in touch before anything happens.

Can you show us your setup?


Hi Sorry for the delay in replying  these are photos of my meter.

Thank you 

Userlevel 7
Badge +1

Hmm… Just a bog standard E7 setup with a local timeswitch…

OVO has a lot of experience with replacing those. Try asking the Support Team in the morning to do a manual booking - it might work that way.

Thank you, excuse my ignorance but what do you mean replacing? What are the options. I still want to keep my economy 7 

Userlevel 7
Badge +1

You’d still have Economy 7 - Smart Meters exist which support this.

However, your current meters are well past their sell-by date - the Certification on them usually lasts around 10 years and you’ve had them since 1997. If they remain in place, they’ll slowly become more and more inaccurate over time.

Is replacing with a SMERT2 the only way of keeping my Economy 7 tariff. 

Thank you for you advice it helps me understand better I will phone the support team tomorrow.