How to connect the NEST thermostat (controller) to the Vaillant Ecotec pro stove

Hello forum members.
I have a problem with connecting the Nest3 generation controller (regulator) to the vaillant ecotec pro single-function oven. The stove is newly set up, so I did not have any driver installed before. I would like it to be possible to independently control the heating of domestic hot water and central heating. I think that this help will be useful not only to me because nesting is becoming more and more common
Thanks in advance for the advice
PS in the attachment photos of the stove inside and a heat link for connection

Write exactly what boiler model you have - Vaillant ecoTEC pro:
VCW xxx / xx, i.e. a 2-function boiler - heats the DHW through flow.
VC xxx / xx, i.e. a single-function boiler - heats the DHW in the tank.

If you have a 2-function boiler, you can only use the central heating control. You do not have to control the DHW here, because if you do not open the tap, the DHW does not fly
If you have a 1-function boiler, you can control the CH, and you can do some trick with the DHW control, you only need to write whether you have an original Vaillant temperature sensor plugged into the DHW tank.

Thanks for the answer..
The stove is Vaillant VC246 / 5-3 Ecotec pro 1F and when it comes to the sensor, it is the original of the Vaillant (At least that's what the seller says - it is not yet plugged into the tray, but tomorrow it will be)
Oh, the stove is on the Belgium and Spain market, but it probably doesn't matter

And do you have a Vaillant weather regulator for it, for example Multimatic 700?

I do not have - I planned to set up this 3rd generation Nest with Heat Link to which the furnace is connected. My brother also has one, only he has a combi oven but he is fine with the application even

So yes - you have two solutions:
1) You leave the Vaillant domestic hot water sensor attached to your ankle in the middle of the boiler and only on the boiler you set the DHW temperature that suits you, but the water in the tank will always be monitored (non-stop) - here we cannot interfere with Nest controller on what day of the week and at what time we have active monitoring of the water in the tank. Heating the central heating, and more precisely unblocking the operation of the central heating boiler, can be performed by Nest by connecting its contact responsible for heating (1-2-3) to the strip in the boiler (RT 24V) in place of the jumper. You connect two wires to the boiler and Nest - the rule is that when Nest gives a signal for heating, there must be a jumper on the RT 24V strip in the boiler, i.e. Nest must close the circuit - you probably need to connect contacts 2-3 in the Nest. You can use the meter to check on which Nest contacts the transition appears when the heating is turned on, or at 1-2 or 2-3, and where a short circuit, we connect the wires from the RT 24V boiler. Just remember that the contacts in the RT 24V boiler are not supplied with ~ 230V voltage - this is only the so-called voltage free contact. Nowhere in the photos of this Nest I have not seen if it gives any voltage on its 1-2-3 contacts, or is it just a changeover contact. Jumper and unlock the heating mode, opening - we block central heating heating. Of course, you need to set a certain temperature of water for the radiators on the boiler. Unfortunately you do not have reg. weather and water temperature for radiators you have to determine yourself. For a condensing boiler, the lower the better, but when frost comes, you will probably have to increase the water temperature for the radiators.

2) You connect the central heating control as above. If you want to control DHW heating by Nest, you have to do some research. Unfortunately, Vaillant has its own E-Bus data protocol and it doesn't work with the Open-Therm that Nest has. But in Nest there is a contact similar to that used for heating CO (4-5-6) and we can use it.
In this case, we will not use the original Vaillant tank temperature sensor - we just do not connect it. But we need a capillary thermostat - for example something like this: Afriso or Salus . Its sensor (capillary) is put into the DHW tank, where there is a place for the sensor. Set the temperature you want in the tank on the thermostat. The thermostat contacts are connected to the plug in the Vaillant boiler, described as C1-C2 - it is a white "large" plug, which lies loosely inside the boiler next to the "small" plug, where the original Vaillant tank temperature sensor is connected. Operation of the C1-C2 contact causes the boiler to start in the tank charging mode, i.e. the switching valve in the boiler switches to the tank and the boiler increases the water temperature so as to quickly heat up the DHW tank. When the water temperature in the tank rises to the value set on the thermostat with the capillary to the value we have set, the contact in the C1-C2 boiler will be opened and the boiler will stop working for DHW heating. You connect the entire control in series with the contact in the Nest (probably 5-6), so that when the DHW heating is turned on in the Nest controller, there is a short circuit. Here again you have to check with the meter which contacts give a short circuit when there is a signal for DHW heating in Nest: 5-6 or 4-5. Remember again that you can not apply ~ 230V voltage to the C1-C2 contacts. The only disadvantage of this solution is that in the boiler diagnostic codes d.04 you will not be able to see the exact temperature of the water in the tank.

Nothing.
I will try to connect it so that I have DHW control because I care about it.
It will be hard for me to find such a specialist at home, so I will try it myself, as instructed by your post.
And if I succeed, I put the bottle on :)

Added after 1 [minutes]:

At the beginning I have to get this thermostat with a capillary.
And to work ...

Added after 27 [minutes]:

So I plug this thermostat with a capillary into this contact in the photo. ?
The most important thing for me is the application control of DHW heating because I work on a business trip and I could remotely set by Nest to which tank to be heated because after connecting it will be possible?

I thought you were more interested in controlling the central heating, i.e. what temperature at home, at what time and on what day.
What exactly do you want to do with this DHW control? Because, for example, I am a supporter of 24/7 access to DHW. Due to this Nest, you can only block the operation of the boiler on DHW, e.g. at night or at some time intervals during the day or night. Just remember that you will not be able to change the DHW temperature via Nest. Temp. You set the hot water only on the thermostat and Nest decides whether to monitor this temperature or not.
Enter also what container you have: company / model / capacity.

The container is alatus 300L and all the data is in the photo.
If possible, I would also like to control hot water, because as I said, I work on a business trip and I do not need hot water for the whole week. Only, for example, when I was to come back, I would like to turn on the DHW heating through the application and nesta.
Is it possible to reconcile the Co and CWU mobile control with this set at all?

Such a possibility as you write would be enough for me.
the set temperature would be "stiff" and I would just like to turn on the heating via applications, for example 3 hours before my return

toomekk24 wrote:

Such a possibility as you write would be enough for me.
the set temperature would be "stiff" and I would just like to turn on the heating via applications, for example 3 hours before my return

In that case - I highly recommend connecting the DHW to the Nest

Of course, CO too. You will also be able to activate the heating to a comfortable temperature before your arrival.

And what else will be connected to this tray?
He has a few more coils.

That's why I care about it and the original internet module for Vaillant costs over a thousand, plus a driver. As for the coils, one is for a traditional furnace because until then I used it, one now will be for gas and one will stay for dollars, if installed. And the question is whether I will be able to change the CO temperature via the Internet or will I be left with a fixed value, as in the case of DHW, and only the on-off function. I mean controlling the application from outside the home

Added after 1 [minutes]:

Not dollars, but solar

toomekk24 wrote:

Will I be able to change the central heating temperature via the Internet or will I be left with a fixed value, as in the case of domestic hot water, and only the on-off function. I mean controlling the application from outside the house

Only as in the case of DHW - fixed function on / off.

If you wanted internet control, you could have taken the Vaillant eRelax driver. He is a weather-internet controller. It collects meteorological data from the area (outside temperature) and then changes the water temperature in the boiler to CO. It has the ability to set schedules for CH and DHW.

If it won't be a hulalo for me, maybe someday I will decide on erelax. I thought that this nest is compatible with vaillants. It is actually this Ebus of my furnace that will remain unused at all, because I plug into the RT 25 connector. And when it comes to DHW and this capirole sensor, I plug into the C1C2 plug and from this holder I pull two more cables to the heat link to position 5 , 6?

toomekk24 wrote:

And as for the DHW and this capirole sensor, I plug it into the C1C2 plug and from this holder I pull two more cables for the heat link to the 5.6 position?

You connect:
boiler (C1) to Nest (5),
Nest (6) to the COM contact on the capillary thermostat
NC (or NO) contact in the thermostat with a capillary tube to (C2) in the boiler.
When all the "relays" (in Nest and in the thermostat) are closed, the DHW heating will start, and when there is an open position, the DHW heating is finished.

And can this solution be applied to my old boiler with a tank so that I do not heat domestic hot water at night and during operation?

But what?
Nest?
Or something else?
Only for DHW? Or to CO too?

Write something more: what do you have (some drivers), what do you want to get etc etc. etc.

I have a vaillant stove with a vrt 330 controller. A vaillant tank with a thermostat is connected to the stove.
Everything is 20 years old. The stove is without ebus.
I would like to program the hopper filling only when I am at home. in the morning 5.30-7.00 and from 16.00 to 23.00.
I also have circulation.
I wonder how to program by adding some controller to heat the hot tap water only at the desired times.
I thought that I needed a programmer for the circulation pump and a switch that would disconnect the temperature sensor located in the tray on the cable that is currently connected to the stove. The temperature of the domestic hot water on the stove is controlled with a knob.
Maybe at a low cost I will be able to reduce gas consumption when I am not at home and I do not use domestic hot water.

You probably have an original Vaillant DHW sensor that works analogically, not as a thermostat. If so, it is plugged into the boiler with a small rectangular plug.
You can do an experiment: remove the ankle and see if the boiler will not heat the DHW. Then plug it in and check if it turns on. If it works, you can put a relay on the sensor cable and control it.

I checked it. This is. after disconnecting the heating, it turns off after reconnecting it, it starts to heat the water in the tank.
What relay should I buy and how to connect it so that I can only heat when I want?