On Sat, 29 Jan 2005 14:28:31 +0000 (GMT), "Dave Plowman (News)"
wrote:

In article ,
wrote:
I have a Honeywell Room Thermostat in the lounge which has two wires
(each with a red and a black inside so four inside) which go to the
heating control box in the airing cupboard.

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!
--
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