Connecting Owl Intuition cw to Vaillant EcoTec boiler

[degsy41]

Hi,

I have an Owl Intuition cw internet controlled thermostat and would like to connect it to my Vaillant EcoTec boiler.
The boiler currently has a VRC470 connected to a wiring pannel which is in turn connected to two valves controling the central heating and hot water.
I have installed the Owel central heating and hot water controllers on the wall near to my boiler and added the hot water controller thermostat to my hot water cyclinder dry pocket. Its detecting the water temp OK.
What I would like to know is do I need to connect the ON/OFF switch cable directly to the valves or can I connect to the wiring panel? The Vaillant diagrams I have are not that clear. I would prefer to connect to the wiring panel if I can but the VRC470 has its own connector into the wiring panel so its not a case of remove the ciurrent cable and replace.

thanks,

Degsy.

 

[ChewChew]

Hi Degsy,

It seems that the Owl system would replace both your existing VRC470 and wiring panel. That’s a shame as I believe the VRC470 has weather compensation capabilities which you would loose.

The Vaillant controls connect to the boiler via their proprietary e-bus system and the Owl connects much like Honeywell S-plan or C-plan using a switched 240Vac (or 24Vdc) connection to the boiler. Have a look in the electrical installation part of your boiler manual.

 

[degsy41]

Thanks ChewChew.
The Vailant wiring panel seems to connect to a motarised valve though (maybe it connects to the boiler also) as does the switch for the hot water (differnet valve).

The owl does do weather compensation but only via internet derived weather reports and not an actual weather sensor like the VRC470.

 

[ChewChew]

The owl does do weather compensation but only via internet derived weather reports and not an actual weather sensor like the VRC470.

That’s interesting. However, the Vaillant weather compensation adjusts the flow temp to the rads based on a function of room temp, outside temp, and desired temp. This allows the CH to run at as a low temp as possible to maximise condensating in the boiler to maximise efficiency. You will lose this capability unless the Owl has a way of communicating CH flow temp to the boiler.

I assume the wiring panel is Vaillant also? If so, search Vaillants site for the installation manual (VR61 or VR65??) and you find the wiring diagrams.

 

[degsy41]

Yes, it is a vaillant wiring centre. All vaillant added by my gas fitter.
I also have solar panels so wanted one system to view/control them all, solar, electricity, central heating and hot water tank. Owl was the only one I could find to do all of them.
thanks for your help.
So the wiring centre doesnt have any way to add external controls?

 

[ChewChew]

So the wiring centre doesnt have any way to add external controls?

I don't think so. Mine (VR65) does not.

Find the part number of yours. If VR65, its a no. If its another, then Google the manual to check.

 

[simond]

There are ways of controlling the heating by interrupting a link on the PCB with the VRC470 if you have an Ecotec Mk2, we do this with Evohome.

With a VR65 and a desire to control the HW, not so easy. You could potentially use the wired cylinder stat option on the VR65 (instead of the thermister VR10) and then use the Owl to interrupt the cyl stat call for heat for HW control and monitoring - but we haven't tried this.

A lot of work for arguably no result. The boiler would be less efficient with the VRC470 taken out, the Owl has no boiler intellegence, at the end of the day it is just an on/off. Going back to 1970.

Steve Jobs invented one device that can monitor an unlimited range of technologies, it's called an iPhone.

 

[degsy41]

I was wanting to be able to control my heating and hot water via a network connection. the only way to do this and keep the vaillant weather compensation is to use the vaillant vSmart but they are £500. way too much.
How much difference does the weather compensation etc have? is this the only difference between the VRC470 and a standard thermostat?

 

[0ldskoolskater]

Hi Degsy41,

What did you do in the end about this?
I am in the same position albeit with a VRC Four thirty and it would be helpful to know what you decided to do.

Cheers

Oldskoolskater

 

[degsy41]

Hi Oldskoolskater. Sorry for the late reply, I don’t remember this site telling me I had a response to my posting.
As yet I still have the VRC470.
I could get the vsmart but as far as I know it uses internet based weather metrics rather than a more accurate sensor on the north face of the house.
Shame Vaillant couldn’t be bothered to design this properly.