Viessman 4 pipe setup with zoning using OT

[iconboy2021]

I’m in the process of looking into the Viessman 4 pipe system to use with the Heatrae Sadia Megaflo and the Vitodens 100W system boiler I have.


Currently, I have two Nests zoned for upstairs and downstairs, would I be able to use multi zone with the 4 pipe setup - would I then be able to use OpenTherm using this configuation?

I would like to the the ability to use the weather compensation with the system boiler too.

I take I would need the following:


Weather Compensating Kit (DHW Cylinder Demand Terminal Box Included)

Weather Compensating Kit (DHW Cylinder Demand Terminal Box Included)

Z007933, Viessmann, Weather Compensating Kit (w/t connecting lead and terminal box)

viessmanndirect.co.uk

DHW Cylinder Sensor Unvented

DHW Cylinder Sensor Unvented

7179114, Cylinder Temperature Sensor for DHW Unvented (G3 compliant)

viessmanndirect.co.uk

Questions?

Would I be able to make use of OpenTherm using two nest thermostats?
Would I need to use Viessman controllers + programmer?
Is multi zoning possible with the 4 pipe system?


As always, thanks in advance.