nest controller wired to a vaillant 837 combi boiler

[jonny1]

Morning

Could someone take the time to confirm my wiring is correct please.

1. From the boiler ive taken a live neutral and earth to the heatlink

2. From the boiler ive taken a cable from the 230v rt connection to number 3 on the heatlink (call for heat)

3. Ive linked the live and 2 terminal at the heatlink

4. Ive taken a 2 core from the heatlink to the remote stat

5. Ive taken the link out of the 24v rt connection at the boiler

Thanks

 

[Agile]

I cannot help thinking that a weather compensation controlled would have been a better choice for your boiler.

Tony

 

[muggles]

Sounds good to me. Is it a new install?

 

[jonny1]

Hello Tony

It isn't my boiler, i supplied the circuit for it then the customer wanted me to wire this controller that he'd bought. I think he liked the thought of controlling the heating from his phone!

 

[jonny1]

Yes andrew, plumbers ripped out old boiler and cynlinder and installed a combi.

I just wanted to confirm that the call for heat connection was the 230v rt connection and not the 24v rt connection..

 

[muggles]

You can use either - you get out of Terminal 3 whatever you put into Terminal 2

 

[jonny1]

Thanks Andrew do you mind telling me why you would use either the 24v or 230v option?? Are some boilers call for heat connections only 24v or only 230v ??

 

[Agile]

I would always wire a stat to the 24v circuit by my choice. So there are not 230v cables around.

However, because virtually all installers always use the 230v connections I do the same.

That ensures that any future people looking at the system don't find anything they cannot follow.

Accidentally putting 230v into the 24v connections is certain death to the PCB.

Tony

 

[Agile]

Your friend would still be better having a weather compensation system as they can save some gas consumption and give better comfort.

Unfortunately, they are quite expensive.

But you can also control them with a Nest for web access for anyone who loves gadgets and is not restricted by what he spends.

Tony

 

[jonny1]

Thanks eveyone for your input

 

[St0rmer66]

But you can also control them with a Nest for web access for anyone who loves gadgets and is not restricted by what he spends.

Tony

Suppose there is nothing stopping you just using the Nest/Hive/alternative as a remote switch (e.g. 30 degrees set for on, 5 degrees for off) and then having the weather compensating controls actually doing the room temperature control.

 

[muggles]

Thanks Andrew do you mind telling me why you would use either the 24v or 230v option?? Are some boilers call for heat connections only 24v or only 230v ??

Personally I always use the 230v as you can then use a single five-core flex for power and switching. You could, of course, put mixed voltages down one flex but it's not really the done thing