"Frank Watson" wrote in message
...
On Wed, 27 Aug 2003 09:11:13 +0100, "Mike Faithfull"
wrote:

"BigWallop" wrote in message
...

"Frank Watson" wrote in message
...
How to make one CH radiator come on and off at set times?
Ideally, I guess I'd like a TRV with a built-in timer - but I guess
that might be unlikely..

So what is the cheapest, simplest way to do it? It's for a bathroom
rad, which I only need on for a couple of hours in the morning.

Thank you

Frank

Hi Frank,

A motorised valve run from a separate timer switch would do the job.
The
valve would be fitted to the pipe supplying that one rad' and be
connected
to a nearby power supply. You'd only need to use the motor supply and
leave
out the micro-switch connections.

I can see how such an arrangement could turn the rad OFF when everything
else was working,

Why not? You can turn a radiator off manually, so it must be equally
feasable to turn it off osing a motorised valve, no?

but .... What about the boiler controls? And are you
expecting this one radiator to have its own individual circuit complete
with
pump from the boiler? Doesn't sound very practical ...

Why would a raditor need it's own individual cirquit before it can be
turned on and off?

Frank

It all comes down to *exactly* what you want to achieve. In your original
post you said that you wanted to make one radiator come ON and OFF at set
times. This implied that there may be times when you want ONLY this radiator
on without any others being on. In such a case, you clearly need to make the
boiler and pump come on at the same time!

If what you *actually* want to do is just to turn this radiator OFF when all
the others are on, and NEVER to run it on its own, you can achieve this with
a motorised valve controlled by a timer.

However, before doing this, make sure that there are no circumstances where
this radiator is the only path between the boiler flow and return. Depending
on system design, you may need to install a separate by-pass circuit.

Roger