Economy 7 - Off peak switches have power during the day

Mantis_Toboggan

I'm having an issue that I suspect is caused by my economy 7 smart meter, but EDF are being less than helpful and claiming it's not an issue on their end.

My set up: I have off peak switches that power the storage heaters and the water heater, so each unit is wired to two switches: one off peak and one that has power throughout the day, only for boost functionality as far as I know..

It had been working fine since I moved in a few months ago but recently I noticed that my water heater was turning on during the day, but I always have the regular power switched off and only leave the off peak switched on, so that it only heats up at night when the second tariff kicks in. So I went and checked one of the storage heater's off peak switch and sure enough, it also gets power during the day now.

I called EDF and they were saying that there should be a timer(or something?) inside the house that controls the off peak wiring/switches, but that makes no sense to me, as far as I know the smart meter also controls when the off peak switches become live. I've checked and there are not timers/devices neither where the consumer unit is or in the airing cupboard where the water heater is.

My smart meter has 5 wires: three are marked L (one is red, two are grey), two are marked N (one black and one grey). I assume the black and red are L and N in from the grid, and that the three grey ones are the ones going out into my flat, with one of the grey L being just for the off peak switches. 

Am I wrong? 

It only started doing it a couple of weeks ago and I haven't touched anything

Here's a pic of my "smart" meter:

GibbsRule_No3.

I am with EDF and have E7, old style meters though.  I keep telling them my E7 is still live at 10.15 am at present but they don’t believe me.  They also tell me that it should be  a straight 7 hours on, never has been, has always had so many on, then off in the middle of the night, then back for the remaining time of the seven hours first thing in the morning, handy to warm the rads and water during the start of the colder weather when I get up, I put it on, rather than leaving it all the time..  Obviously at present it benefits me and I have tried warning them.

dunstonh

I am no expert when it comes to wiring and will leave that bit to others.  However, not all economy 7 installations work by switching circuits.   Some work by timers.    

And that is the case with our economy 7.  The devices have their own timers and the meter just switches over from rate 1 to rate 4 at a given time for all electricity used.   The timers have to match the meter time.

MWT

Mantis_Toboggan said:

My smart meter has 5 wires: three are marked L (one is red, two are grey), two are marked N (one black and one grey). I assume the black and red are L and N in from the grid, and that the three grey ones are the ones going out into my flat, with one of the grey L being just for the off peak switches. 

Am I wrong? 

It only started doing it a couple of weeks ago and I haven't touched anything

You are not wrong, it you have a 5 port SMETS2 meter then the switching of the day/night rate circuit is entirely controlled by your supplier through their configuration of your meter and the ALCS built into it.
I would suggest checking your meter readings to make sure the night rate register is incrementing when you find the 'off-peak' circuit live...

Mantis_Toboggan

MWT said:

Mantis_Toboggan said:

My smart meter has 5 wires: three are marked L (one is red, two are grey), two are marked N (one black and one grey). I assume the black and red are L and N in from the grid, and that the three grey ones are the ones going out into my flat, with one of the grey L being just for the off peak switches. 

Am I wrong? 

It only started doing it a couple of weeks ago and I haven't touched anything

You are not wrong, it you have a 5 port SMETS2 meter then the switching of the day/night rate circuit is entirely controlled by your supplier through their configuration of your meter and the ALCS built into it.
I would suggest checking your meter readings to make sure the night rate register is incrementing when you find the 'off-peak' circuit live...

Thanks, just to make sure I understood it correctly, does that mean that whenever it comes on during the day, the whole flat is being charged at the cheaper rate? 

My understanding is that during normal circumstances, the entire flat switches to the cheaper rate at night, and that also the off peak outlets also get turned on (as a way to power older appliances, such as the water heater or old storage heaters that didn't have the capacity to use a timer to determine when to turn on). Is that accurate?

I just assumed that the cheaper rate timer and the off peak circuit timer were independent from each other, but if that's not the case then it's not really an issue for me.

MWT

Mantis_Toboggan said:

I just assumed that the cheaper rate timer and the off peak circuit timer were independent from each other, but if that's not the case then it's not really an issue for me.

It should be switching the power and the meter register together, so yes, it is is working correctly but at the wrong time then you will be getting all of your use recorded at the low rate while the heating is on.

I do suggest checking the meter though to make sure, as there are some ways it could be getting it out of sync.

mmmmikey

Hi, there are 3 common configurations for E7 wiring:

1. The house has a completely separate set of wiring circuits for storage heaters and an immersion heater. This cicrcuit is switched on and off directly by the meter so you know with absolute certainty that these are only ever using cheap rate night power. The circuits will be dead during the day. This is the kind of meter that you have and if the storage heaters are coming on during the day there is either a fault with the meter, or it has been connected in incorrectly, or you have non-standard domestic wiring - e.g. maybe the heater you checked is connected to a bog-standard circuit rather than the off during the day E7 circuit.

2. As 1 above, but instead of the meter switching the sockets on and off, there is a central timeswitch that does this, located somewhere near the meter / fusebox (aka consumer unit or distribution panel). In this case, the central timeswitch has to be set to the same times as the meter otherwise there is a chance that the storage & immersion heater will use day rate electricity for part of the time (=bad!)

3. As 2 above, but instead of a central timeswitch, each individual storage or immersion heater has it's own individual timeswitch which has to be set to match the meter with the same risk as 2.

A couple of other considerations:

1. If you're on E7 the whole house gets cheap rate electricity at night and the whole house gets expensive electrcity during the day. The timers and/or extra circuit are just there to make sure that the storage heaters and immersion heaters only use cheap rate electricity.

2. It is very common to have 2 immersion heaters. One at the bottom of the cylinder that only runs on cheap E7 every night as above. The other at the top which is connected to "normal" house wiring which is designed as a boost or backup. The idea is that if you run out of cheaply heated hot water you can give it a quick boost whenever you need - but you need to be aware that if you do this during the day you will be using expensive elctricity.

Hope this helps in some way?

Mantis_Toboggan

mmmmikey said:

Hi, there are 3 common configurations for E7 wiring:

1. The house has a completely separate set of wiring circuits for storage heaters and an immersion heater. This cicrcuit is switched on and off directly by the meter so you know with absolute certainty that these are only ever using cheap rate night power. The circuits will be dead during the day. This is the kind of meter that you have and if the storage heaters are coming on during the day there is either a fault with the meter, or it has been connected in incorrectly, or you have non-standard domestic wiring - e.g. maybe the heater you checked is connected to a bog-standard circuit rather than the off during the day E7 circuit.

1 is definitely my case, the storage heater has two switches: on for the off peak circuit and one for the regular "always on" circuit, which it uses for the boost functionality. Same as the water heater which also has two heating elements.

Thanks for the details though, it definitely helped to confirm that my initial assessment was correct.

Mantis_Toboggan

Update: was finally able to get through to someone helpful at EDF, they looked into it and it was indeed a config issue on their end. They updated the off peak times on the meter remotely and the issue is now resolved.

Thanks again for the feedback.