Which System Boiler - that fully modulates?

[rossyl]

Hi All

I would be most grateful for a suggestion of what System Boiler to buy.

I would like a system that can control :
- system boiler
- fully modulated by EvoHome

The larger system involves
- unvented HW cylinder
- one zone of UFH
- Smart TRVs
- two zone of Elec UFH

Everytime I think I've found a boiler it seems there's some issue with the level of control Evohome is given via OpenTherm.

Grateful for advice

Thanks

[rossyl]

To answer my own query, after much research.

I'm going to have a Domestic HW Priority System, with a System Boiler and an Unvented HW Cylinder.

It does not seem that Evohome can work with Vaillant or Viesmann's weather comp, and therefore Evohome is unable to benefit from weather compensated temperature flow rates.

On that basis, I'm going to stick with the boiler manufacturers own controls.

[Richard]

Boilers that do work...

Intergas, Alpha, Atag.