Replacing wired room thermostat for Google Nest smart thermostat

[Harry_W]

Morning, hoping someone can help. I've got a Tower wall thermostat that is not working and have been thinking about upgrading to a Google Nest smart thermostat. I have a Potterton Titanium 28 combi boiler.

Is Google Nest compatible and a straight swap?

 

[Stuckinarut]

Hard to tell but it doesn't look like anything is connected at the boiler end. Nest isn't a straight swap, and how are you planning to power the thermostat itself? Or were you thinking of the Nest E? Which would be a straight swap, providing the wiring is ok at the boiler end.

 

[Harry_W]

I meant the Nest E as the boiler is fitted inside a kitchen cupboard so no room to install a receiver next to it. In terms of wiring at the boiler end, what do I need to check?

 

[Stuckinarut]

I meant the Nest E as the boiler is fitted inside a kitchen cupboard so no room to install a receiver next to it. In terms of wiring at the boiler end, what do I need to check?

You have brown (L), Grey (N) and green/Yellow (E) there are 2 terminal connections above those which are live and switched live - are there wires in both?

 

[Harry_W]

There's wires in the side closest to the PCB but none in the other side.

 

[RandomGrinch]

You have brown (L), Grey (N) and green/Yellow (E) there are 2 terminal connections above those which are live and switched live - are there wires in both?

Looking closely at the photo, there is a black wire from the triple and earth in the Live Return terminal 1 of the boiler.
It may be difficult to see, but with a visible grey and brown core, there is almost certainly going to be a black one hiding as well.

Is Google Nest compatible and a straight swap?

As above...

were you thinking of the Nest E? Which would be a straight swap,

Although, just to note: Nest thermostats are getting difficult to come by at the moment, while we're waiting for the 4th gen stats to roll out over here (if they ever do!).

 

[ericmark]

Well spotted @RandomGrinch and yes, I would not be fitting Nest unless forced to. Nest USA have temperature senders so you can monitor multi-rooms, but they were not released here, Nest does not link the TRV heads, yes it says it works with Energenie, but it doesn't so unless using hot air central heating, or it's an open-plan house, then Nest seems to have lost the plot. I fitted Nest as with two wires, I can control both CH and DHW, and supply power, using 3rd Generation, and using Nest e there is also a reason. But I have fitted Wiser as well as Nest, as I needed better control.

The picture says line must be taken from terminal 2, which is clearly not the case, so what next?