Any Sparkies know about Economy 7?

[Fallout]

Another random thread! I moved into this house about 3 months ago. It is economy 7 electric only. I've finally got round to finding instructions for our immersion heater timer, because I've heard it flick on at 11:30pm (when our eco7 comes on), and several times through the night. It seems like a waste of money to heat water at the start of the night. A couple of hours at the end of the eco7 time slot would be fine for us.

Anyway, I still don't get how wiring works with eco 7. At first I assumed it was one set of wiring throughout the house, and when the eco7 started and the meter switched over, it just sent power down all the same wiring using the cheaper tariff. Makes sense to me, except I noticed our storage heater sockets do not work at all until the economy 7 tariff starts. So to me thats saying there is two lots of wiring 1. for normal tariff and 1 for night tariff. So that means anything using power when eco7 switches on, but plugged into the normal tariff line will still get charged at normal rate (not eco7). Right? That's what I now understand to be the case.

So why is it that, when my curiosity got the better of me, and I decided to take my immersion timer off the wall and see how it was wired up, there is only 1 set of mains cables going into it? I would've expected 2 sets (one for normal tariff and 1 for eco7, that only goes live when the eco7 meter switches on). The reason I expect that is because I can hit a button on the immersion timer to get heat during the day whenever I want.

Basically now I am concerned it's not wired right and when it's heating the water at night, it's still using the normal day electricity (which costs more than an ancient chinese ming vase), rather than the eco 7.

So it's either:
1. Hooked up to a day tariff only, yet only powering up at night, but I'm getting rinsed for cash by shoddy wiring.

OR

2. Although my storage heaters are connected to eco7 wiring that only goes live at night, somehow this is connected to wiring that is live with normal tariff by day and live with eco7 tariff by night.

Anyone get this? Does my head in, I tell thee. :smt120

[thefallenangel]

Look for 2 fuse boards and all will become apparent. You probably have 2 use boards one by a time clock which gives you your economy 7 and the other is a normal supply.

[tigersaw]

You have a meter with HI and LO digits?
If so then during economy 7 all your leccy is cheap rate.
Some are a simple timer running 7 hours through the night, later ones may split the 7 hours into 2 chunks dependant on the load on the grid

[Drew Carey]

I am not a sparky, but we used to have an identical system in our last place.

Our system we could not "stop" from coming on - without turning it off completely. It would automatically come on at the start of E7. Our immersion etc however was a brand new state of the art one - which had almost zero heat loss - ie you could touch anywhere on the outer tank and not feel it being warm.

When the heater kicks in - it heats the water that was cool (as apparently the tank keeps hot and cold seperate) and transfers it into the hot tank as it is heated. As a result - the heating is not on for the full economy 7 period - just the point it is heating the cool water.

Hence it is very economical as uses the elecy when needed. Our heaters worked on the same - we had brand new top of the range storage rads that charged from 12 till 7 and then gave a low constant heat throughout the day.

It worked out well for us, considering we had no gas - our elecy bills were on average around £55 per month to cover heating, water, cooking, appliances etc.

[Fallout]

Been looking at the meter, and I think I get it, kind of, maybe. Yeah, it hate hi and lo, or on my meter it reads R1 and R2, and I assume R2 is the evening tariff. I guess I assumed the cable infrastructure changed the tariff, but apparently it's either switched by radio signal or a built in timer.

Anyway, there are 4 outputs from the meter, and I think one of them goes into a little black box which may be specifically for the storage heaters. So, maybe, perhaps, kind of, possibly, when the meter is in day rate, it sends power out of the normal output, and when it goes to evening rate, it sends power out of the normal output and to the storage heater circuit.

I really love guessing. :rolleyes:

@Drew - I'm dealing with less state of the art stuff here, but overall I'm happy enough with it. Have to do lots of nob twiddlin to balance the heat output, but I'm good at that. :smt003 All our bills have been estimated at £50 so far. Not looking forward to the first real bill now I've given them the real readings. [-o<