Replace existing thermostat with WiFi version

[Deleted member 267285]

I was using GC version. The question is from my old thermostat which terminals correspond to the new "GC" terminals...

You, me and Ian have already answered this. However Com from Danfoss into 1 on GC, NO from Danfoss into 2 on GC, Ian has actually stated it doesn’t matter if you get these 2 the wrong way round.

What you don’t have presently is a permanent live and permanent neutral from Danfoss to transfer into GC.

 

[mfizz]

You, me and Ian have already answered this. However Com from Danfoss into 1 on GC, NO from Danfoss into 2 on GC, Ian has actually stated it doesn’t matter if you get these 2 the wrong way round.

What you don’t have presently is a permanent live and permanent neutral from Danfoss to transfer into GC.

So I've got a couple of things I can do. Very near it I have a light switch, chances of it having a neutral, I'll have to check. But technically insulation permitting I should be able to draw a wire through.

Option 2 is further down a bit, there is a socket similarly I could draw it or I could wire it up directly with a plug maybe?

Was wondering though, wouldn't it be possible for the live at least to use a jumper from what would be the old com on danfoss, 1 on GC. Isn't that a permanent live?

 

[Deleted member 267285]

I wouldn’t be using switches or sockets. I’ve seen some new thermostats wired on a plug, but usually low voltage ones. Yes the live, com would be a permanent live, but the neutral should be part of the same circuit.

 

[mfizz]

Why would you suggest not using a socket, is it because it would not be isolated when you turn off from the spur near the boiler? There is an alternative, but it would require some work perhaps less so than completely brand new wiring. If you look at my original picture, you can see there is a wire coiled up at the back (grey). I assume this would have been used if it was not a battery operated programmer. I could find where the junction box is and use that instead. Chances are it was a 3 core wire and that last wire is unused.

 

[ianmcd]

I was using GC version. The question is from my old thermostat which terminals correspond to the new "GC" terminals...

I already tols you in #9

 

[ianmcd]

Why would you suggest not using a socket, is it because it would not be isolated when you turn off from the spur near the boiler? There is an alternative, but it would require some work perhaps less so than completely brand new wiring. If you look at my original picture, you can see there is a wire coiled up at the back (grey). I assume this would have been used if it was not a battery operated programmer. I could find where the junction box is and use that instead. Chances are it was a 3 core wire and that last wire is unused.

The L&N supply to the thermostat MUST be supplied from the heating system eithet the fused spur or the boiler itself

 

[mfizz]

Thank you both ianmcd and chris_w for guiding me in the right direction.

I managed to locate the junction box and to my pleasure it appears I might be good from a wiring point of view, if I use a jumper to power the thermostat. I can see there are neutral wires going into junction box from the 2 motors controlling the water flow. The wires from the thermostat I can see are also in the same terminal. The wire itself in the thermostat is coiled up at the back not connected, so would be just a case of stripping and wiring it up.

I'm quite certain that's the case, but posting a picture just to confirm and make sure before placing my orders.