On Tue, 18 May 2021 10:54:03 +0100, "NY" wrote:

snip

Storage heaters fail because they give out their heat too quickly in a
morning (even when the heat output control is turned right down) and there
isn't much left by the time you get home from work in an evening.

So you mean 'some / the current range of storage heaters fail ...' as
it shouldn't be beyond the abilities of man to make them better? ;-)

Also there
is no way of programming the heat output to increase shortly before you get
home from work so the house is up to temperature.

See above.

snip

My storage rads are 'smart' in that they turn on automatically, after
receiving power (E7), but only when they determine that they still
need a recharge to be able to absorb the maximum required input to
(predictably) last them though the day.

No predictive system is ever perfect of course but they generally did
a good job, especially when the temperature was changing smoothly.

eg. In the summer they didn't come on at all, in spring / autumn they
might be on for a while towards the *end* of the E7 cutoff time (so
lasting best throughout the day) and during the winter they were often
on most of the E7 period and generally kept the room warm for the
entire day (correct size / room match, good insulation and efficient
thermostatic control).

Unfortunately, something went wrong in them all after a good few years
(15-20, I suspect the main relay) as they would repeatedly 'clonk'
when they should have just pulled in the once. I did track down a
replacement relay but it wasn't cheap and the postage from abroad made
it even more so. Things may be different now and so I may re-visit
that one.

Alternatively I could now probably integrate them into my Home
Automation system and make them even more 'intelligent. ;-)

Internal temperature probe measuring the core. External probe for the
room, controlling a servo on the heat outlet control flap and a solid
state relay for the heater element (it doesn't matter if it gets
warm). ;-)

Cheers, T i m