teleswitch faulty

On my second return visit to the flat that seemed to be having problems I fitted an 'hours run' meter on two of the heaters and sure enough they both recorded spot on 7 hours per night over a period.

 

On my second return visit to the flat that seemed to be having problems I fitted an 'hours run' meter on two of the heaters and sure enough they both recorded spot on 7 hours per night over a period.

 

ah yes. I guess all I really need to know is that we are getting our contracted allocation of lowrate. I am not sure why I thought I needed to know when it was coming on!

 

That depends.
As long as all of your off peak appliances are powered by the contactor it's fine. Many immersion heaters seem to run on a time switch on the 24/7 circuits. So actual time period of E7 needs to be known to get the best benefit.

 

Indeed. However, if my immersion is anything to go by, 1-2 hours is generally all it needs to heat it 'up to temp', and never more than about 3 hours (if the contents start totally cold) - followed by occasional 'top-ups' of insignificantly short duration (usually no more than 1-2 mins) for as long as there is power. It's therefore not usually difficult to time the 'power on' period for the immersion within the period which is guaranteed to be at 'off peak' price.

Kind Regards, John

 

No it's not difficult but no point in starting at 23:30 if the tarriff doesn't change until 00:00.

And to keep an eye on the time clock in case of a power outage. I've had that issue with a tenant who would turn the immersion switch off in the morning to save power.

 

Sure - but it just needs some thought, and a little (but, I suspect, very little) 'gambling'.

If the immersion is supplied by a 'dedicated' time-switch from a supply which is not switched by a 'tariff-controlled contactor' then, with remotely-controlled tariff changing (e.g. teleswitch) there is always a theoretical risk that the tariff will switch to 'full price' for a period (theoretically anything up to 2 hours, with a 22:00-07:00 'guarantee', as mentioned by Simon) whilst the immersion is active, but I would think that is very unlikely to happen 'in the middle of the night' (since that is likely to be a low demand period).

Hence, in my case (never needing more than 3 hours of primary operation), if (with a "22:00-07:00 guarantee) I set the 'on-time' of the immersion as, say, 02:00, or even 03:00, (with 'off-time' at 07:00), that would almost guarantee that most/all of its usage would be at cheap rate (with a very small risk that some might be charged at 'full rate'), whilst allowing brief top-ups right up to 07:00.

In passing, never having had a remotely-switched tariff, I don't know, but I'm not sure that Simon's mention of "7 hours between 22:00 and 07:00, in no more than two blocks" is necessarily typical. With my locally-switched E7 (pre-programmed non-'smart' meter), the off-peak period is 00:30-07:30 GMT (hence 01:30-08:30 BST in Summer, since the meter doesn't understand the change to BST!)

Kind Regards, John

 

Indeed, in one of my remotely-switched setups, we had similar. 'On' would be somewhere between 00:00 and 00:30 GMT, and 'off' would be somewhere between 07:00 and 07:30 GMT (corresponding to the on time to give exactly 7 hours). In one other property I'm pretty sure the hours were 22:00 to 00:00 (or thereabouts) and then 03:00 to 07:00 (again, GMT, and always giving the full 7 hours).

Another flat we were in was E10, so that came on in the afternoon too, but of course that's not what we're discussing here.

As you say, for anything on a timer, rather than using the switched circuits, we just set the timer to come on around 4AM, to be sure to get 'cheap' electricity.

 

As I said, one theoretically could not be totally sure with 'rules' such as Simon suggested, since the cheap period could theoretically be, for example, 22:00-04:00 plus 06:00-07:00, such that the first two hours of one's immersion's use (when most of the energy would be used) would (if it's timer set to come on at 04:00) be at 'full price'. However, as I said, I think it extremely unlikely that it would ever be in a supplier's interests to have a high-price period in the middle of the night (hence lower-priced periods at other times).

Kind Regards, John

 

That sounds a bit like different groups switching.

 

I guess it could be, I didn't really pay enough attention at the time to see if they all had the same group ID on them (I do recall they had it written on them though). I guess one thing that was odd though was they *my own* timing would vary by upto 30 mins each night. In fact, now I remember, this particular one *would* change to allow for BST, but it did it a few days after the actual changeover. I'm sure at the time I worked out a pattern (i.e. it was always some specific time after the change), but as I say, this was 8 years ago so the specifics have vanished from my memory.