Need quick answer about wire colours to thermostat

Richard

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Sep 13, 2010, 10:22:46 AM9/13/10

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I need to put in a new cable to thermostat that is affixed adjacent to
immersion heater.

Have boiler which either is set to heating, or water.

Is there a need to put in same cable, I mean with same colours.

Present colurs are black, brown, green/yellow.

Off tho B&Q in about 40 minutes time.

Thanks

Richard

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Sep 13, 2010, 10:24:20 AM9/13/10

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I say immersion heater, I just mean cylinder tank.

Mike Clarke

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Sep 13, 2010, 10:34:28 AM9/13/10

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Richard wrote:

Well, just about all the cable at B&Q will be that colour. If the thermostat
is on the hot water cylinder you probably ought to get heat resistant cable
though.

--
Mike Clarke

ARWadsworth

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Sep 13, 2010, 10:34:15 AM9/13/10

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"Richard" <no...@ntlworld.com> wrote in message
news:8f6qgq...@mid.individual.net...

That is an odd colour scheme. Is there a core (grey) that has been cut right
back?

You need 0.75 or 1.0mm heat resistant flex. The number of cores needed
depends on how many terminals you are using on the cylinder stat and if the
stat needs an earth.

4 core heat resisistant flex will cover all you needs.

Cheers

--
Adam

Richard

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Sep 13, 2010, 11:06:46 AM9/13/10

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Okay, I'll certainly get heat resising.

I'm looking at the diagram I made.

It's one of those systems with two motorised valves. One for Water,
other Heater.

WATER CIRCUIT

Is blue from neutral to motor valve, brown from motor valve to cylinder
thermostat, black out from thermostat to DANFOSS 3E Timer, which derives
a live feed from the boiler.

HEATER CIRCUIT

I had to change the colours because originally three core red, blue,
yellow was being used.

I rewired that so it's now:

Is blue from neutral, brown from motorised valve to room thermostat,
white out from thermostat to DANFOSS 3E Timer, which derives a live feed
from the boiler.

In other words Water and Heating have same colours, except it's a black
wire live feed from DANFOSS Timer to Water thermostat, whereas it's a
white live feed from DANFOSS Timer to Heater thermostat.

Just wondering whether it's alright to have black wire to feed water
thermostat. I mean, that's live. But that is the original colour.

Richard

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Sep 13, 2010, 11:18:24 AM9/13/10

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Actually, white could be grey I supppose.

Room stat is fed live with a grey.

Cylinder state is at present fed live with a black.

I could get three core grey, brown, black. But that would mean both
stat's have same coloured live feed.

Is it permissible to put inicating sleeves on wires to identify?

Dave Osborne

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Sep 13, 2010, 6:59:17 PM9/13/10

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Just don't use blue for anything but neutral and you'll be OK.

See here:

http://www.diyfaq.org.uk/docs/Sundial-Wiring-Rev1d-2nd%20Edition.pdf

black, brown, grey, white, orange wires all used for live.

Richard

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Sep 14, 2010, 3:09:56 AM9/14/10

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Okay.

Well, in the end I got blue and brown. What I will do is eventually
source a better cable, probably black and brown as original and replace
with that. I was just in a hurry yesterday.

ARWadsworth

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Sep 13, 2010, 10:34:15 AM9/13/10

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"Richard" <no...@ntlworld.com> wrote in message
news:8f6qgq...@mid.individual.net...

That is an odd colour scheme. Is there a core (grey) that has been cut right