On Sat, 26 Aug 2006 10:24:40 +0100, The Natural Philosopher wrote:

The Wanderer wrote:

snip

That alone won't give rise to the symptoms you describe. If the system has
been wired properly, then the controller overides any other auxiliary
switches (like the thermostat, the aux switches on the valves) in the
circuit.


Completely WRONG. The controller does not have the power to drive the
boiler. The controller drives the thermostat and the valve motor: The
switches on the valve body control the boiler. That is why they are there.

Yes, you are correct, I had mis-read the wiring diagram I was looking at.

--
the dot wanderer at tesco dot net