On 12/11/17 13:05, T i m wrote:
On Sun, 12 Nov 2017 12:41:34 +0000, Tim Watts


Normally you use a designated radiator.

So this would be on all the time, no stat-valve etc?

Yes.

And with lockshield valves both ends so normal users don't fiddle.

Or if you
don't want to (or don't trust it not to be fiddled with), you could do
as I did and put a pressure bypass in, which should only open to protect
the boiler pump.

Ah, that makes more sense and as you eluded to above, less chance of
being 'fiddled with'.

It will be interesting to see how it all went on Friday (when the
plumbers were due back to replace both motorised valves) and whilst
they were there the other day I overheard talk of 'one of the
motorised valves not being moveable by hand' ... but are they all (as
they could have been different makes / designs)?

Usually they have an override lever that can be pushed and dropped into
a locking slot, for when the motor fails.