Worchester Bosch DT10RF to Nest/Pre-heat

[Longclough]

I am looking to replace my current thermostat (DT10RF) on my WB 440CDi Highflow combi boiler with Nest. I am looking to verify that I understand the wiring correctly.

The have attached a picture of the boiler connections and Nest.

I believe I need to wire the nest as follows:

ST10 Ls to Nest L
ST10 Ns to Nest N
ST10 Lr to Nest 3
Link Nest L to Nest 2

Can someone confirm that the wiring proposed is correct?

I also wanted to ask if there is a way to use pre-heat with the Nest or if this facility will be lost following installation of the nest.

Thanks in advance.

 

[hertsboilers]

Yes.

Can't set pre heat from Nest

 

[ianmcd]

No your wiring is wrong.

ST10L to nest L
ST10N to nest N
ST10 LS to nest 2
ST10 LR to nest 3
no links

The nest in this instace will only control the radiators the HW pre heat is controlled by the ECO button on the boiler and wont be affected, you will however have to
disconnect the DT10RF from the boiler or this will over ride the nest when installed

 

[hertsboilers]

No your wiring is wrong.

ST10L to nest L
ST10N to nest N
ST10 LS to nest 2
ST10 LR to nest 3
no links

The nest in this instace will only control the radiators the HW pre heat is controlled by the ECO button on the boiler and wont be affected, you will however have to
disconnect the DT10RF from the boiler or this will over ride the nest when installed

His wiring is still working.

 

[ianmcd]

His wiring is still working.

yes but if he switches the heating off at the boiler it will cut the power supply the the nest receiver, it needs a permanent live

 

[Longclough]

Hertsboiler and ianmcd for your input. Ianmcd that was originally what I was going to do with the live and neutral until I realised there was a alternative on ST10 and was thinking it may be easy to have less wires in the ST10 terminals. You have however pointed out the downside if using the Ls and Ns terminals.

As for preheat, with eco mode controlling it is pretty much either permanent preheat or no preheat, which is fine.

 

[ianmcd]

The nest will not affect the pre heat it is just a switch that turns the heating on or off