Economy 10 problem

[achookang]

Hi,

I live in a rented flat with storage heaters and a hot water boiler powered by off peak electricity (Powergen said its the Economy 10 tariff).

My boiler has two immersion heaters with separate switches in the cupboard. They wern't marked so by trial and error I discovered that one works all the time and the other one only goes on at night when permanently switched "on".

So far so good....

Two days ago I woke up with no hot water, and after some experimentation I find that the storage heaters now also do not heat up (They've been off recently since its good weather..)

I can still heat up my hot water boiler using the other "always works" switch but only manually.

My questions are:

1. How could only the night time cheap electricity stop working.
2. How can my supplier (Powergen) fix it.
3. If I use electrical appliances during the night time when it ought to be cheap electriicty will it still be cheap? e.g. if I turn on the water bolier "manually" at 2am in the morning??

I have inspected my meter (which is very confusing) which seems to have

3 rates, numbered 1-3, which when I phoned Powergen they told me 1 was night, 2 was day and 3 was "stored heat" (didn't really understand that bit). The meter still seems to change from day to night i.e. during day the rate 2 and 3 readings are flashed alternately and marked "current" and in the middle of the night rates 1 and 3 are marked "current".

Sorry if this is a bit vague - I'm not really familiar with any of this stuff.

Any explanations or advice will be appreciated.

[Owain]

Usually the top one, for topping up during the day. It will be expensive if you leave this running all the time.

Leave that one on.

You have probably got two consumer units - one for the night-only circuits. That will be connected to the meter through a contactor (relay), timeswitch or teleswitch. Maybe the timeswitch has stopped.

By correcting the fault.

Most modern economy tariffs apply to all electricty taken during the cheap period. Check that with Powergen. If it is the case, it might be worthwhile putting your washing machine on a timer, if you don't mind it running during the night. (Some washers have a delayed start button to do this.)

The good news for you is you live in a rented property, so it's your landlord's responsibility.

Owain

[achookang]

Thanks for the hints.

I (or the landlord) would need to get an electrician to sort out, or is it more like something Powergen should be sorting?

I have arranged for someone from Powergen to come out and look at the meter (although they cant come for two weeks!!) but maybe its not actually a meter or supply problem, but something "internal" in the flats wiring or something????

[Owain]

It depends exactly where the fault is. Have you checked your consumer units and made sure there are no MCBs/RCDs tripped?

The meter, timeswitch/teleswitch/contactor are usually sealed and would be Powergen's responsibility.

Have you agreed how much your landlord is going to reduce the rent because of your increased electricity bills? :-)

If you can upload a photo of your switchgear to a website and post the URL (photos aren't allowed in uk.* newsgroups) we might be able to identify your set-up.

Owain

[Colin Wilson]

Load switching equipment is often *not* the responsibility of the supplier - its often the customers' equipment.

[achookang]

OK. I'm not sure exactly what you need pix of, but if you go to

you will get a directory listing of some jpegs. Hopefully the pix therein will help. If you need pix of other things please reply and I'll try and sort it.

Alan

[Martyn Pollard]

Alan, When was that unvented cylinder installed and who did the job?!

Martyn

[Tim Morley]

Your main switch is marked 24h and o/p. o/p will be the off peak supply. Your meter looks like it is sending out 2 supplies. Has your distribution board (fuse board) got 2 main switches on it? Or have you a photo of it?

[achookang]

if you mean that small cylinder on the lower right from the big tank, it was presumably installed when the flats were built along with everything else. The flat is only 1 year old (approx.)

[achookang]

the fuse board is one of those modern things with a bank of switch type things that presumably get tripped if there is a surge and can be manually switched back again.

There is one separate red bank of three switches marked "non RCD protected": (1) off-peak immersion, (2) storage heating, (3) storage heating. [there are 2 storage heaters in the flat]

Then there is a green bank marked "RCD protected": (1)sockets (2) sockets, along with a master RCD switch.

Then finally another red bank "non- RCD protected": (1)lights (2)lights (3)smoke detector (4)central heating (5)immersion (6)cooker, and a main switch for that bank.

So, yes, there seems to be separate switches for the off peak immersion and the regular immersion.

None of the switches had been "tripped" by the way, they were/are all in the on position!

Alan

[Owain]

It appears that you have a combined meter/teleswitch which is responsible for switching on the off-peak supply at the appropriate time. This is why you have two phase wires (reds) out of the meter into your main switch.

I am *very* concerned that you appear to have three separate switches on that main switch, switching the neutral separately from the phase. Having a single-pole switch in the neutral is very very very bad.

I would have expected the neutral to split at the main switch, feeding two DP switches, and then feeding two consumer units.

An electrician would open the main switch and test for voltage on the

24hr and O/P terminals at the appropriate times - unfortunately this means a night call-out for the electrician.

Do you hear a click from the meter/teleswitch at the start/end of the off-peak period? which would be the internal contactor kicking in and out.

I think it's a supplier problem, and loss of supply/teleswitch failure should be a lot more urgent than a 2 week wait, more like 2 hour response.

I am assuming it's nothing as mundane as the jumper to the off-peak bus-bar in the consumer unit having fallen out of its terminals.

Owain

[Martyn Pollard]

The unvented cylinder is the larger tank. If its that new, you should have a blue benchmark card for it. Do you have it and has it been completed?

Martyn

[achookang]

Now you have me worried. Can you explain a bit more, why you have concerns about this switch arrangement? (in non-technical terms if possible - I have no experience with this sort of thing). Is it dangerous? In what circumstances? What needs changed?

I haven't tried listening. I don't know what time the different charging periods start/end - any ideas? Is it always the same in different geographical areas, and at different times of year? (and even with different suppliers??) Also the meter cupboard is outside the flat in the hall.

I'm going to try and contact Powergen again and see if I can persuade them to come a bit quicker.

I'm afraid you've completely lost me there.... :-)

Alan

[achookang]

As a tenant, I haven't been left any such documents by the landlord. What would the benchmark card tell me?

Do you have concerns there is something wrong with it? How could I tell? Could it have any bearing on the original problem of no off peak electricity supply? (also affects the storage heaters)

[Owain]

What is bad about having a single-pole switch in the neutral is that, if the neutral is switched off, things stop working, and it might be assumed that the circuit is dead. However, the phase (live) is still connected and the circuit is still very much alive and waiting to zap anyone unsuspecting.

Are they three switches, or does the black one not do anything?

Owain

[achookang]

Owain,

thanks for your continuing advice.

The black switch has a metal bar/wire inside it connecting it to the adjacent red switches. So if you move the black switch, it also switches the red ones. I didn't fully switch them, since I'd have to reset a bunch of timing appliances in my house (what a pain) but I could see from moving it a bit, and closely inspecting it that it was connected as I noted above.

I guess this is the safety mechanism so the neutral and live all get switched together to avoid the situation you descibed.

Alan

[Martyn Pollard]

The person installing an unvented cylinder must be 'competent'. In this case they must have done relevant training and hold an unvented certificate. From the picture, the plumbing of the safety discharge pipework does not appear to meet those regulations - but I might be wrong. I had wondered if it had been checked by the the BCO, especially if its a new build.

Since you are not paying for the maintenance, I would ask your landlord to get an approved person to come and give it a safety check and also look at the problem with immersion heater. Specifically, ask the person about the regulations for the safety discharge.

[mockendo]

Also check out

for some useful info on the tariff.