Vokera and Neat Wiring

[dgrallying]

I have a electrician wire in a Gen 3 Nest state and the heating doesn’t work and he can’t get back for over a week.

I can’t seem to find a link from the boiler to the nest thermostats.
Can anyone give me some guidance so that I can get this boiler up and running with the nest

many thank in advance

 

[RandomGrinch]

Hi,

The install looks as if it could work - Only if your boiler accepts mains live switching!
Although, I don't like the stretch on the live (brown) cable.
And he has used the earth cable and grey, for the 12V connection to power the nest 'stat; not exactly best practice! - extra low voltage cable should be completely isolated from mains voltage cabling.
It looks like the black cable is the 'Call to heat'.

However, the information you have given so far doesn't really help us troubleshoot your problem!

What model is your boiler?
Did the electrician leave the system in a working condition?
Have you long pressed the button in the middle of the heatlink? Does the heating come on if you do?
Are the boiler controls for heating, set to always on?

Those are some questions to start!

 

[MeldrewsMate]

I'm impressed that the installer managed to get two cores into the Nest terminal strip - they are barely large enough for one!
The lack of indicative sleeving asks questions of the installer's standards, which is why I'm not referring to him/her as an electrician.

Where does that 5 core flex lead to? Please post a photo of the insides of that junction box, indicating which is the 5 core flex if it's not obvious.

 

[ianmcd]

It is wired completely wrong, get someone else in , that wiring is so wrong on many sections, if you keep messing around with that you will need a new PCB

 

[RandomGrinch]

Oh, you may want to read this thread:

https://www.diynot.com/diy/threads/vokera-wireless-thermostat-wiring-help.515776/

But it looks as if that is where you got the photo from in the first place!

As @ianmcd states, if that is your boiler (a Vokera Vision 30C), it will only accept voltage free switching. Connecting the Nest in that state could destroy the boilers PCB.

 

[dgrallying]

I have pulled the cables out of the box so that you have a better sight of the cables

 

[ianmcd]

well you seem determined to do it rather than get a pro in

remove the link between Live and 2 in the heat link, DO NOT make any links between live and anything, your boiler has 24v dc switching do not put mains voltage on that connection , remove the link wire indicated and one end goes to terminal 2 on the heatlink and the other end goes to terminal 3 ,either way round doesnt matter, then L&N from the boiler to L&N on the heat link, I havent a clue what your so called electrician has done but have the feeling this is going to be expensive

 

[RandomGrinch]

I would strongly recommend you get a new electrician!

Your system has two Nest heat links and two, 2-port valves.
Do you know what each do?
This may not be as simple as connecting the nest directly to your boiler.

Apart from that, the wiring is potentially dangerous.
There are mains voltage and extra low voltage (12V DC to power the 'stats) connections in the box using cable with no sheathing and no labelling.
Mixing any of these up could be dangerous and expensive!

These appear to be the DC connections to the Nests, in very confusing colours:

 

[fezster]

OP has 2 x 2 port Danfoss valves. The MV will most likely be doing the volt free switching.

 

[fezster]

To clarify my post above - the MV should be doing the volt free switching. I havent tried to make heads nor tails of the picture of the wiring to ascertain whether it is or not.

I agree with posters above that the 12V wiring should be kept completely separate and labelled accordingly.

 

[RandomGrinch]

As far as I can make out so far, the nests have been wired with (black wire) call to heat operating the (live brown) two port valves, so theoretically connected 'correctly'


But then I'm lost; it looks like it's actually live switching on the orange and gray from the 2-port switches, rather than 'volt free' switching.



But who knows what those wires really are with this electrician

...again, I reiterate - call in a new electrician!

 

[vulcancontinental]

Get a better electrician in. That's the bit we all agree on.

Wire the switching orange and grey at 230v but DO NOT connect them to the black link in the boiler control box, there is an accessory relay that clips into the boiler that will be connected to the 230v controls and to the PCB at the 24v it is designed to switch.

If you run 230v next to 24volts in cables you can get an inducted that will keep the boiler on even though there is no demand.

Get a better electrician.

 

[ianmcd]

I have a electrician wire in a Gen 3 Nest state and the heating doesn’t work and he can’t get back for over a week.

I can’t seem to find a link from the boiler to the nest thermostats.
Can anyone give me some guidance so that I can get this boiler up and running with the nest

many thank in advance

say where in the country you are and we might be able to recommend someone in your area , you are really out of your depth on this one