Hoping to de-modernise flat heating system.

[Dave Liquorice]

No the easiest way is to feed the CU for the heaters via the main (switched) contacts of the time switch.

The OP also needs to look at his electricity bill to see if he is still on an E7 tarrif. Hopefully he is(*) and essentially all that is required is the above wiring change at the board and installation of new storeage heaters. New high heat retention heaters will need a permenant supply but with two rings and three heaters that should be possible to derive from the rings. I suspect one ring is kitchen and the other rest of flat. Put one heater on the "kitchen" ring, the other two on the "rest of flat" one.

(*) All consumption during the off peak period, that the meter still "knows about" from the time switch, will be at the lower price. Without the large heating load this isn't likely top be economic, broadly you need to use 2/3 of your total consumption during the off peak period to break even on E7.

[Dave Liquorice]

Smart meter fanboy?

Or doesn't realise the time switch has a "Main circuit 100(12) A" switching capabilty as per it's rating plate. B-)

[spuorgelgoog]

A very sensible question.

The existing meter needs an external timeswitch or teleswitch to (a) change the meter from rate 1 to rate 2; and (b) to connect the heating load only at off-peak times. It only has L and N supply, and single L and N for load.

More modern meters include their own timeswitch or radioteleswitch (or smart meter equivalent) and have separate Live outputs for 24-hour *and* off-peak, so there is no need for any timeswitch or contactor to control the heating load, and the heating load switching cannot get out of synch with the meter rate changing.

This is also a bona fide application of smart metering - the heating load charging periods can be moved to accommodate varying demand on the grid.

It also makes for a much neater installation with usually only 1 henley block needed to split the neutral (and not even that if a dual tariff board is fitted)

Owain

[Andrew]

And quite fat cables going in and out of it :-)

[spuorgelgoog]

But that timeswitch is used for the supplier's rate change and is connected to the *unmetered* supply. The consumer does not bear the cost of running the timeswitch motor. The consumer must use either his own timeswitch, or a contactor.

Owain

[ARW]

The flat will have had an EPC report on it before the OP bought it.

However I still cannot see a couple of 450W panel heaters would be up to the job.

[ARW]

The average weight of a cat is given as 3kg in that link.

When I took my cat to the vets last month after a night out fighting (the cat not me) he weighed in at 7.1kg.

So maybe you only need half the cats?

[Mike Halmarack]

Wonderful stuff Owain but I'm sweating cobs just trying to understand it, let alone do it. That will have to be the job of someone much more electrical.

[Chris Green]

Where?

[Dave Liquorice]

The main circuit contacts in the time switch are just that, a set of contacts. There is no connection between them and the supply used to drive the clock and coil to operate those contacts.

[Tufnell Park]

I would just replace the Aldi panel heaters with higher output plug-in ones say 2kW. Shouldn't cost more than £100.

[Robin]

I asked as I hadn't seen or heard of a supplier fitting Smart Meters twin outputs, preferring to leave the switching on the consumer's side. I'd got it into my head (possibly from a rogue dispiration particle*) they deprecated anything but a single output these days with a view to tariffs with more than 2 tiers.

*the nasty cousins of inspiration particles that :(

[Alan]

They heat up around 100kg of bricks inside the heater, which are then wrapped in insulation, with vents to open when the heat is required. They arent great. Newer ones are better, better insulation,and a fan is used to get the heat out.

[spuorgelgoog]

You may be correct, but in the current installation the contact and the clock share a neutral - there may be an internal link of course.

Owain

[jeikppkywk]

None in mine either., No rockwool either, very unusual semi rigid very bright white insulation, allegedly the same stuff used in the space shuttle heat shields etc. Very light.

[Dave Liquorice]

All there is is a L and N for the clock and coil and a low current Aux circuit (2 A) output to the meter to tell it which register to use. None of the main circuit wiring is in place.

[Roger Hayter]

Is this common for the signalling link between the timeswitch and the meter to be a neutral alone? On mine it is a single live (they are already both connected to the incoming neutral.) is it possible that the link from the timeswitch to the meter should be two wires; or even a single live inapkpropriately implemented with black wire?

[jeikppkywk]

Very expensive way to heat a house unless its super insulated and even that is very expensive with an existing house/flat.

Air sourced heat pumps arent that expensive and much cheaper to run, about a third of the running cost.

[spuorgelgoog]

I think so, it helps to prevent abstraction.

It's a switched neutral - I checked the wiring instructions for that meter model.

Owain

[Mike Halmarack]

I only wish you were here to do the job Owain. But such a wish is a sacrilege for a DIYer.