Confused about what wiring is required for using Economy 7

plumtreebabe

hi folks,

thought I had it sussed - I've just bought 4 storage heaters from ebay, ordered Economy 7 meter from EDF, and rang electrician to install heaters on separate wiring circuit as advised in my earlier thread. I had also hadplans for using the immersion, washing machine, tumble dryer etc at the cheaper time. However, my electrician has told my husband (I wish now I'd taken the call) that any appliances intended for economy 7 including water heater and washing machine would have to be wired separately into the Economy tariff. I thought this was how it used to happen not how it happens now? Will I have to choose which tariff my sockets are wired to?

Thank you!

jalexa

plumtreebabe wrote: »

my electrician has told my husband (I wish now I'd taken the call) that any appliances intended for economy 7 including water heater and washing machine would have to be wired separately into the Economy tariff.

That is not right, I assume there has been a misunderstanding (or the electrician is not competent). With E7 *all* existing wiring automatically charges cheap rate during during cheap rate hours and day rate during day rate hours. That includes all sockets (e.g. your washing machine, tumble drier etc) and your existing* water heating (but you are responsible for ensuring that appliances and water heating are only switched on during cheap rate times) unless you want to pay the day rate.

* full E7 spec water heating has a seperate main element connected *only* to the cheap rate supply and a top-up element available 24 hours per day under your control. Unlikely you have that unless you have upgraded your water heating.

Swipe

plumtreebabe wrote: »

Will I have to choose which tariff my sockets are wired to?

Only the E7 storage heaters should be directly wired into the E7 circuit and any boost switches to the daytime circuit. The immersion heater should also be E7 but only if it it has duel heaters (one for off peak and a boost for daytime) otherwise, if it's a single element heater, it should be wired into the daytime circuit.

The electrician is either talking out of his backside or whoever spoke to them on the telephone has misunderstood what he has said. When the utility distributor comes to wire in the E7 meter they will be able to advise you properly but, as stated, these days, all sockets should be wired to make use of the night time rate when it switches over.

Richie-from-the-Boro

Agreed, clueless sparky, or the O/P's lack of understanding of how E7 works at the cabling level.

O/P .. .. the confusion arises because although you do need two different circuits, but do not need a different supply. The The 3 new requirements are :

- (1) the E7 supplier meter
- (2) the E7 storage radiators
- (2a) the storage radiator ring main
- (3) a separate E7 type two element water cylinder
- (3a) with a separate 'off peak' electricity supply
- (3b) with a different E7 water controller

To get your 'head around' the problem imagine your current system :
- your leccy comes into the house to a non E7 fusebox/DU and then 'goes around the house

To get your 'head around' the problem imagine your new system :
- your leccy comes into the house to a fusebox/DU, and then inches from it to a second E7 only fusebox/DU
- cabling goes from the E7 only to the radiators and the bottom of two elements in the water cylinder
- your old top element immersion heater switch is taken away and an E7 controller is put in its place

The E7 water controller has both your old non E7 and your new E7 only wired into it and an internal switch automatically switches from day to night cabling and stops you ever being able to accidentally or deliberately use both supplies simultaneously.

The new heavy duty E7 on its own dedicated circuit and your old system including your immersion heater continues as it did before. Both of the two different circuits run at the arranged times on cheap rate. Usually at the new meter install an additional set of tails is installed for the exclusive use of the E7 circuit.

Hope this helps your understanding - I'm off to watch the Liverpool match on ESPNHD

bengasman

jalexa wrote: »

... With E7 *all* existing wiring automatically charges cheap rate during during cheap rate hours and day rate during day rate hours.

No it doesn't.
Dual tariff has dual meters and thus two separate circuits; one is one 24/7 e.g. sockets, the other one goes on and off e.g. storage heating.

jalexa

bengasman wrote: »

No it doesn't.
Dual tariff has dual meters and thus two separate circuits; one is one 24/7 e.g. sockets, the other one goes on and off e.g. storage heating.

I'm afraid you have missed the context of the question and my response (and the intent of the word "existing"). The OP was concerned that appliances such as washing machine and tumble drier would need "to be wired separately into the Economy tariff".

If you are saying the OP already had a pre-existing storage heater circuit then that is not stated by the OP in this thread, though I agree my response could have been clearer on that point.

Your contribition is no more no less pedantic than it would be for me to have responded only to point out with E7 there is only one meter with two registers.

HappyMJ

bengasman wrote: »

No it doesn't.
Dual tariff has dual meters and thus two separate circuits; one is one 24/7 e.g. sockets, the other one goes on and off e.g. storage heating.

Can you elaborate a bit more on what you mean? I have E7 electricity but only 1 meter and only 1 circuit. I have individual timers on each appliance and on the immersion heater that I have to set to come on at night if I want to use E7 or not.

edit:crossposted with jalexa....

bengasman

How can you have two tariffs with only one meter? In other words: how would the supplier know which part of your use was on high tariff, and which part was on low?

jalexa

bengasman wrote: »

How can you have two tariffs with only one meter? In other words: how would the supplier know which part of your use was on high tariff, and which part was on low?

Stick to gas:rotfl:

HappyMJ

bengasman wrote: »

How can you have two tariffs with only one meter? In other words: how would the supplier know which part of your use was on high tariff, and which part was on low?

I read the meter then I press the button and read the next reading then press the button again and get a third reading which is the sum of the first 2 readings. It's all in one meter. There are no additional circuits at all. I do not have storage heating and I do not have a dual immersion cylinder.

frugalmacdugal

Hi,

bengasman wrote: »

How can you have two tariffs with only one meter? In other words: how would the supplier know which part of your use was on high tariff, and which part was on low?

HappMJ has explained in post 10 how his meter works, you can also get this type, a two rate meter, controlled by a time switch,



Electric 2 - Rate Meter



If your meter has two rows of figures like this, it’s a 2-rate economy 7 or white meter. One set of readings is for your lower priced night-rate electricity - this will be marked ‘low’ or ‘night’. The other is for your day rate and is marked ‘normal’ or ‘day’.