Thermostat swap

[Penfold01?]

Hi I am trying to swap my danfoss tp5000si thermostat to a drayton wiser smart thermostat however I am confused by the wiring. Could someone help as these wires make no sense to me what do the 4 wires for please.
Thank you in advance.

 

[JohnD]

the 4 wires for

pull the camera back and take a wider pic. I can only see the two wires in use that will be L and SL.

I could guess what the others are, but show us.

How many wires does your new stat need?

You haven't got a multimeter, have you?

 

[Penfold01?]

Hi the other 2 wires are the earth and a random grey wire unknown they are in a terminal block pushed into the wall. Only the 2 wires you see are in use

 

[Penfold01?]

I also dont know how many wires the new stat needs as it's a standard back plate. And no I dont have a multimeter

 

[Penfold01?]

wiring diagram for back plate for new stat

 

[ianmcd]

you will need to run a new cable to your new thermostat, your existing thermostat is battery powered your new one is mains powered and will need a live and a neutral, the existing other two wires go to 1 & 3 on the new stat, it MAY be possible to use the existing wiring but that is just a maybe, all depends on what you have and if you could use the spare grey wire as a neutral but if you current switching is low voltage you will need another cable run