How do i undo this, feeds to boiler control unit

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Hi,

I was trying to switch my boiler control and in my haste undid all the wires behind the boiler control unit.

How do I reconnect them. So the new wiser unit can send demand for either HW or CH?
The connector blocks restores power to the combi, there is a cylinder upstairs. 2 room thermostats

Baby sleep deprivation has fried my brain.


Black & Grey wires to to boiler.

Other wires:
1 Blue
2 light brown
1 brown
1 black with brown cover
1Grey with brown cover

Also pics of cables behind each room thermostat attach
 

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Colours mean nothing, and with a combi boiler in the main you do not control the domestic hot water (DHW) but you say hot water tank and two zones, so assume you're using a three channel wiser?

The hub will likely go close to the motorised valves, which has cables with them, so their colours can be relied on.

I have not really worked out why some homes have mains powered zone valves? With the Wiser the TRV heads make the TRV into a motorised valve, so no real reason to have zone valves.
 
Thanks for the reply.

Ill look to wire the Wiser into the control centre. It is a 3 channel version.

Unfortunately no smart Trvs.

Here is the wiring currently, are these standard colours?
 

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Here is the wiring currently, are these standard colours?
At the wiring centre the three black cables with 5 conductors each will be standard (google S-plan+) , connected to three zone valves. You can take an educated guess on the the neutrals and earths, subject to testing. With a multi meter and Wagos and possibly some extra cable you should be able to establish the identities of the other conductors.

You have made life immeasurably harder for yourself by neglecting to note which wire went where on the old controller/stats before disconnecting, and referencing these to the diagrams on the back of each component.

Quite honestly I think you'd be better off getting someone in with experience of fault-finding on CH wiring systems (some electricians and some boiler guys have the skills required)
 
Nobody disconnects anything by mistake

Best get a spark in who’s familiar with boiler controls
 

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