Storage heater dead - wiring confusion?

[Leave]

One of my mothers storage heaters stopped working earlier this year and now I've been hassled to get it fixed.
All the other heaters are working fine apart from the one in the bedroom.
Looking at the heaters there is a switched fused spur and a switch with flex outlet next to each one.
I checked the fuse it was fine. then took off the switches.
Looking at the fused switched spur, the wires don't go into the supply and load holes, they both go into the supply holes, so the fuse & switch aren't doing anything.
At the switch with flex outlet, the wires coming into it aren't from the sf spur right next to it (checked with meter) and are dead.
Checking other heaters, their flex outlets were live (obviously - the heaters were hot).

I guess the sf spurs form a ring (both side were live when disconnected from the sf spur), but where are all the flex outlets going back to?
Mum has a modern smart meter with an E7 5th terminal, but that wire just disappears into the wall.
I'm confused, can anyone help? That heater has been working fine for years. Temporarily wiring up an entension cable to the terminals in the heater confirms the heater warms up fine, so it's definitely the wiring to that flex outlet that is at fault, but where it goes or what's happened to it is a bit of a mystery.

 

[SUNRAY]

There are a number of ways E7 for storage heaters are wired but the common method is for something like this.

I've drawn some wires to describe the operation.

The reds are 24hr power from the meter to the 24hr consumer unit (in this case the top half of a single unit) and also the black box in the middle.

That is the Radio Teleswitch, it receives a signal via radio and does 2 things 1) Tells the meter to change tarriff via my purple and 2) applies power to the cheap rate consumer unit (the bottom half of the single unit) via my pink

The black box may take different different forms, it may be a timeswitch for example but the wiring is usually fairly similar.

Is it possible to get a pic showing meter, consumer unit(s) and the wiring between them?

 

[SUNRAY]

One of my mothers storage heaters stopped working earlier this year and now I've been hassled to get it fixed.
All the other heaters are working fine apart from the one in the bedroom.
Looking at the heaters there is a switched fused spur and a switch with flex outlet next to each one.

It sounds like you have 2 flexes going into the heater

I checked the fuse it was fine. then took off the switches.
Looking at the fused switched spur, the wires don't go into the supply and load holes, they both go into the supply holes, so the fuse & switch aren't doing anything.

That is usually 24hr power, typically used for the daytime boost function and depending on the age of the heater it may run a daytime fan or control the operation, it may be from the general purpose ring or a dedicated radial but either way it's from the 24hr consumer unit

At the switch with flex outlet, the wires coming into it aren't from the sf spur right next to it (checked with meter) and are dead.

That is usually the the cheap rate supply and comes from the cheap rate consumer unit.

Checking other heaters, their flex outlets were live (obviously - the heaters were hot).

I guess the sf spurs form a ring (both side were live when disconnected from the sf spur), but where are all the flex outlets going back to?

cheaprate CU

Mum has a modern smart meter with an E7 5th terminal, but that wire just disappears into the wall.
I'm confused, can anyone help? That heater has been working fine for years. Temporarily wiring up an entension cable to the terminals in the heater confirms the heater warms up fine, so it's definitely the wiring to that flex outlet that is at fault, but where it goes or what's happened to it is a bit of a mystery.

Pictures please.