On Fri, 27 Nov 2020 15:15:13 +0000, T i m wrote:

On Fri, 27 Nov 2020 13:55:42 +0000, Caecilius
wrote:

snip

My plan is to put this temperature controller between the timeclock
and the heater, and set the heater thermostat to something like 25C as
a fail-safe.

Or have both functions (clock / stat) combined?

Yes, no reason not to combine the two functions. But that's not
essential.


Has anyone found or built something like this? I'm sure I can't be
the only person who want a constant overnight bedroom temperature
without running the main house heating.

https://www.timeguard.com/products/c...r-time-control

I'm not sure the actual switch is silent though but it is very quiet.

It's probably an improvement on the WW2 era bimetalic strip that my
convection heater uses, but I suspect it's still a relay inside and it
probably has a fairly high hysterisis to preserve contact life.
Unfortunately the data sheet doesn't give much information about the
switching method or the operating parameters.

The problem you might have is getting the heater itself to stay on
without it's overtemp or main stat cycling, even though the remote
timer / stat is calling for heat?

I don't think that will be a problem. If I set the thermostat on the
convection heater to, say, 25C then it shouldn't activate unless the
room is unpleasantly hot. And if the internal overtemp operates then
there's something badly wrong.

I did buy some mains level PWM power controllers with the intention of
mating them with an Arduino and remote thermostats (one on the heater
and one in the room) so that I could manage the power to a small oil
filled rad (that couldn't dissipate it's heat energy fast enough so
would modulate on it's overtemp stat) and manage the room temp both
silently and more accurately (no temperature overshoot etc).

Not gotrountuit yet of course ... ;-(

We've all been there with arduino/pi things I think. I know I have.

Cheers, T i m