Wiring for Honeywell L641A1039?

[dannynolan]

Replacing a non-working thermostat on the hot water cylinder, photos attached.

The old thermostat has blue, green/yellow, brown wiring.

How do the old wiring colours transfer/relate to the new tstat's terminals marked C, 1, 2.

I understand that the new tstat does not need an earth, so what do we do with the earth wire in the flex.

All help gratefully received.

 

[denso13]

Just copy the existing one to the new one, same colours to the same terminals.

 

[RandomGrinch]

Hi,

Your old thermostat didn't need an earth connection either!
The new one is a direct replacement - the wiring should match.
A 3 core mains cable has been used for convenience, the blue and the green/yellow cores should be sleeved in brown - they are both switched lives and should ideally be differentiated from being a neutral, or an earth core.

I hope that helps!

 

[dannynolan]

Many thanks for the replies and apologies for the delay in getting back, we was aht and abaht.

Ok, double checking being electrics and all, the new tstat should be connected as shown in the diagram below, right? (Orange is the nearest we could get to brown)


Many thanks.

 

[denso13]

Yes, that's correct.

 

[dannynolan]

Thanks very much.

Ps you're looking well.

 

[denso13]

 

[ianmcd]

trim back the bare copper on those wires that is dangerous

 

[RandomGrinch]

trim back the bare copper on those wires that is dangerous

Definitely not best practice, and definitely should be cut back (or looped around the screw), but thankfully, not too dangerous in this instance!
It would be likely to cause spurious on/off signals though.

 

[dannynolan]

Appreciate the feedback as ever. We have installed it and will make sure the wires are tidy.

Ps OH is the brains of the operation. Pre Youtube days she completely rewired her dad's house, all the old crap out, plugs and lights downstairs and upstairs, cooker, and new consumer unit, local electricity board test and connect, and all without a cordless drill.

Any extremely organised women out there, there's a career for you.