converting old honeywell controller to wiser controller

24 Jul 2021
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United Kingdom

I'm trying to convert my current heating system to use the wiser thermostat and controller kit 1.

Here is my current controller

PXL_20230105_132317969 (1).jpg

I have the indstry standard backplate underneath which is what I intend on replacing the above with.

Here is the diagram
PXL_20230105_132418323 (1).jpg

The diagram is confusing me slightly. If 1 is supposed to be neutral why is the wire brown?

Is anyone able to tell me which numbers go to which b numbers?

Thank you
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The diagram is confusing me slightly. If 1 is supposed to be neutral why is the wire brown?
Colours mean absolutely nothing in a heating system, although I’d expect them to get this one right, but if it’s working as is and you don’t intend to swap the wires around at the other end (would be better) then do the following (using your numbering system):

1 to N and I would sleeve it blue and double check the integrity of it as it appears torn
2 to L and sleeve brown
5 to Com and tidy the terminal
6 to On and tidy the terminal
Thank you so much Chris. I will do that. What do I need to do wth the earth (9)?
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The earth goes to the earth tether which is the lonely connection bottom right next to your thumb. Call that b7 in your convention.

I would recommend you tidy up the cores to minimise the loose threads. You don't want them to touch each other.
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Also ensure you do NOT put the link in between L & 1 (your b2 & b3) on the back plate.

I would be fairly confident that whomever wired up the original Honeywell got the brown & blue the wrong way around. Can you see the other end of the 3-core cable to check. If you cannot find the other end leave them as is (i.e. the "wrong way around") as it does not matter in powering the Wiser itself. Note it would be important to know which is the live core if you needed to link L & 1 but that's not true in your case.
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