Drayton wiser wiring

6 Jun 2015
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United Kingdom

I've just bought a Drayton wiser to replace my Lifestyle LP241. The old controller had a universal backplate and the central heating is controlled by a wall thermostat.

Can people just help me make sure I get the new wiring correct? Want to disconnect the thermostat as suggested in the wiser instructions.

Currently the thermostat has a yellow wire going from the call terminal. There is a yellow wire to no 4 on the back plate for HW on which I guess is the other end of this wire. If I disconnect this from the back plate do I need something else going to no 4? There is mention in the instructions of a bridge between the thermostat common and call. They also state all wires for the thermostat should be removed from the wall plate. So where should this bridge go and will any of the other wires in the backplate relate to the thermostat? E.g. do the L and N go to the L and N of the thermostat?

Pictures of current setup attached

Thanks for any help!

Read more: https://www.diynot.com/diy/threads/drayton-wiser-wiring.528328/#ixzz5xcvUGe4I


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I don't think that is the other end of the yellow wire. At the stat yellow would normally go elsewhere (valve)

If the wiser does HW too, you should be able to put it where your timer was.
Looking at the instructions, this appears to be the case.
Turn the thermostat upto maximum e.g 30°C for now.

If the wiser is heating only, put it where you stat was.

Once you have it working and understand it, then think about moving wires. (you could put the red and yellow into the same terminal at the thermostat if you wanted) so it was bypassed.

Here is a guide

Last edited:
Normal wiring is the programmer supplies the thermostat switches the motorised valve, and the motorised valve turns the boiler on/off.

To do this the normal way is to use a wiring centre, I.e. junction box, in fact there may be more than one.

So step one is to identify what system you have, Honeywell published a series of systems called C, S, W, Y etc. Some have three port valves, some have two port valves, some simply turn pump on/off.

Some use thermal syphon for domestic hot water (DHW) and some use a thermostat on the tank, others don't. So by looking at the pumps, and valves you can normally work it out.

There is no standard colour code except for the motorised valve, so colours of the valve wires help working out what is what.

I normally start with a drawing of the wiring centre and slowly build up a name base for the wires, don't panic just take it step by step, and slowly you work out how wired.
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This is an S Plan as I have said there are others the 10 way terminal block shown do change in order this is just an example, in this case a bridge 4 to 5 would allow removal of the room thermostat, but the C-Plan has exactly the same connections to programmer and wall thermostat.
In the diagram shown it would need the same bridge wire 4 to 5 but unlike where the motorised valve is used there is very little to help identify the thermostat wires, I have spend many a happy hour trying to identify what system and how wired specially where the installer has used a socket back box and a length of connector block and a blanking plate rather than an official wiring centre. By removing links one only needs 7 connections and seen that done many times and it looks like a rats nest.

upper_wiring_centre_plus_heatlink.jpg Picture of one of the wiring centres in my house, not the easiest to work out what does what, lucky I have a diagram so can easy work on it, but it took some time drawing it all out. In this case using a Nest thermostat, I would not think anyone could work out that wiring from a picture.

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