Existing wiring compatibility

[Danny_gartside]

Hi I’m looking to replace my existing thermostat with a nest product and want to explore whether my existing wiring is compatible. I currently have a Siemens REV23 thermostat and the wiring to the terminals go to point L and L1. There is a black wire to a terminal block behind it but it is not connected to anything. The earth is connected the metal back box in the wall.

any help would be much appreciated

thanks,

Danny

[Jhonleanmel]

Hi Danny_gartside,

Thanks for reaching out. I'd love to know more about this. Could you share a photo of your current thermostat's wiring? Also, you could try our compatibility checker to see if your current system is compatible with the Nest Thermostat.

Thanks,
Mel

[Danny_gartside]

Hi Mel, thanks for getting back to me. Here is a picture of the wiring I have on my current thermostat 

[Danny_gartside]

 

[Markjosephp]

Hello there,

I appreciate your assistance, Mel.

@Danny_gartside, Thanks for posting your thermostat wiring diagram. Wires labeled "L" can be indicator lights. The Nest thermostat uses its LCD display instead of an indicator light, and it does not need this wire.

To determine your systems' compatibility, could you also send us a picture of your system's control panel showing how the wires are labeled? I'll look forward to your response.

Regards,

Mark

[EmersonB]

Hi everyone,

@Danny_gartside I'm dropping by to ensure that everything is covered here.We would appreciate it if you could share with us the information we're asking above. So that we could take a closer look and assist you further.

I appreciate your response, Mel and Mark.

Best,
Emerson

[Danny_gartside]

sorry all i totally missed your replies. When you say control panel, do you mean the actual thermostat controller? If so it slots into the holster at the back and pins connect into the wiring points shown. I can only assume that the wires currently connected must be a switch for basic on/off and the other is a power feed to keep the control panel charged maybe?

[Danny_gartside]

also, the panel can be removed and still operates the heating so i suspect there is some kind of wireless connection to the backplate

[Markjosephp]

Hello there,

I'm sorry for the late reply, @Danny_gartside. Your system might have a circuit board where the wires from your system are connected through your thermostat. Please have a look at this article with a guide on how to check your system wires and let us know if you need more help.

Thanks,

Mark

[Markjosephp]

Hi Danny_gartside,

I wanted to follow up and see if you are still in need of any help. Please let me know if you are still having any trouble from here, as I would be happy to take a closer look and assist you further.

Thanks,

Mark

[Danny_gartside]

Morning Mark,

I think i've checked as much as i can and the photos from above are all that i have available wiring wise so i'm at a bit of a loss to be honest. I'm guessing the wires i have are a live feed to the switch thats activates the boiler as required and in turn it charges/powers the thermostat panel. The current thermostat i have is a siemens REV23 if that helps?

[Jenelyn_O]

Hi folks, 

@Danny_gartside, I saw your post and wanted to chime in — i'm sorry for the delay. I just want to confirm if you're still encountering the issue. Let me know as I'll be willing to assist you further. 

Thanks @Jhonleanmel, @Markjosephp and @EmersonB for assisting this thread.

Best,

Jenelyn

[Danny_gartside]

Hello there, yea I’m still without a suitable answer really that will allow me to progress with an upgrade 

[Jenelyn_O]

Hi Danny_gartside,

Thanks for the update — I'm sorry that this issue hasn't been resolved yet. Could you please tell me in what country you're located? It will help us to identify which Nest Thermostat is suited for your system. 

Best,

Jenelyn

[Danny_gartside]

Hi Jenelyn,

I'm in the UK

[OannaCG]

Hi there! Thanks for letting us know. From the pictures that you sent us, I suspect that you've done the US compatibility checker, as that one is requesting pictures of the wall thermostat. Please access this link, select "United Kingdom" and proceed to test the compatibility of your system: https://goo.gle/3AF4Aei. Let me know how it went.

[Danny_gartside]

Hi...right ok, i've tried that and it suggests straight away that i can use a nest thermostat so all good...thank you

[AlexD]

No worries. The US and EU/UK versions are different and they have different compatibility checkers. I will go ahead and close this thread, but if anything else comes up, make sure to open up a new thread.