In article ,
heating tech wrote:
hiya everyone could someone out their help me please,when i install a
boiler etc and a new room thermostat is to be fitted it can be very
confusing as to what wires are what,plus nearly always only 3 core has
been installed and use the earth as a switched live,i can where
possible change it to a 4 core with the correct colour coding.

Most use triple and earth for this purpose. It's against regulations to
use a bare earth conductor for anything other than earth.

However, if this has been done check inside the CH junction box to find
out how it's been wired - then fit a modern thermostat of the
programmable variety which doesn't need an earth or neutral being
battery operated, and make sure you wire it up without using the ECC on
the TW&E cable for anything other than an earth.

--
*Learn from your parents' mistakes - use birth control

Dave Plowman London SW
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