In article ,
Nick Atty wrote:
Older thermostats have three 'mains' wires - ignoring the earth. A live
feed, a neutral, and a switch return to the pump. The person wiring
yours should really have used a triple and earth rather than two twin
and earths. One wire out of the four will be unused.

And some newer electronic ones as well.

What's the recommended wiring colours to use for this - I put the
receiving end of a wireless pair yesterday and used red for live, blue
for neutral and yellow for switched return. It sort of felt right as
an amalgam of the two colour schemes!

That's what I'd use, but under the old colours the blue should have a
black sleeve on it to denote it's a neutral, and the yellow a red sleeve
to denote it's a live.

--
*With her marriage she got a new name and a dress.*

Dave Plowman London SW
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