Replacing thermostat with Nest - no neutral?

[Gorners]

First of all sorry, I'm loathe to post this as I know the information should be out there somewhere, but I just cannot find it. Pretty sure I know the answer but want to confirm.

Fitting Nest for a family member, boiler is a Potterton Powermax 155x, he simply wants the thermostat replacing like for like, no messing about with the hot water. Attached image shows in wiring setup, point 3 being the main piece of information. So it should be as simple as:

Nest 2 (common) to 27
Nest 3 (call for heat) to 28

Now the exiting thermostat has a neutral, and the diagram states to attach one to N3. Am I correct in stating that this wire is just removed as the Nest doesn't have a neutral?

 

[jackthom]

The heatlink does need a Live and a Neutral in order to power itself up.
The wire you are taking to Heatlink 2 will need to be linked across to Heatlink Live and the Neutral wire will go straight to Heatlink Neutral.

 

[Gorners]

The heatlink does need a Live and a Neutral in order to power itself up.
The wire you are taking to Heatlink 2 will need to be linked across to Heatlink Live and the Neutral wire will go straight to Heatlink Neutral.

Yes I'm aware of that but the neutral that powers the device is not the same as the neutral I'm talking about here that goes to existing stat. It's that I want to confirm if it is just removed either the Newt in place.

 

[jackthom]

If you already have a separate power supply for the Heatlink then as you say the Neutral can be disconnected at the boiler.
The Heatlink should ideally get it’s power from the same outlet as the boiler so it becomes safely isolated from the mains when the boiler system is powered OFF.

 

[Gorners]

If you already have a separate power supply for the Heatlink then as you say the Neutral can be disconnected at the boiler.
The Heatlink should ideally get it’s power from the same outlet as the boiler so it becomes safely isolated from the mains when the boiler system is powered OFF.

Im taking the power supply for the Nest from the existing fused switch to the boiler, not these thermostat terminals. Not sure that would be a very good idea

 

[jackthom]

If the wire in terminal 27 was shifted up to L2 the Heatlink would get a permanent power feed from the boiler regardless of the setting of the boiler timer. Then you wouldn’t need a new supply feed.
Either way I’m sure it will work fine.

 

[Gorners]

To close the loop on this in case someone miraculously stumbles across it, fitted today as detailed above, just disconnected the neutral.