Viessmann 200-W Combi 35kw (New 2019 version) Installed - Advice?

[Brambles]

From what you have described is Evohome controlling the UFH or is it operating in unconstrained operation? I would recommend that the UFH with your boiler would probably be better controlled using Vitodens add on module. It should not be left on unconstrained operation unless the full system is only Combi DHW and UFH.

The DHW temperature is adjusted through the menu function - up to 60 degrees (I think).

Pork Chops comments on Evohome with weather compensation are correct in my experience Evohome deals with the problem, provided that all other parameters are left unchanged.

I would not recommend converting to Open Therm operation until the current system is set up correctly. Your existing Evohome system can easily be configured to operate a Viessmann boiler through Open Therm, but not with the UFH in unconstrained mode

 

[Jamie P]

Hey, i have the 222-F however i cant see anything to say its opentherm
how did you connect honeywell to your 200?

 

[StumblingTrout]

From what you have described is Evohome controlling the UFH or is it operating in unconstrained operation?

We don’t have any underfloor heating - it's an old Georgian house with normal rads in each room.

My understanding of how it's set up from what I can gather from the manual/screen is that the boiler is set to "Continuous operation" which means that flow temp is 70 degrees when the Evohome calls for heat (either on or off) or lower when it's not demanding heat (which from what I can worked out is the 'Reduced Flow' temperature) which was set to 20 degrees.
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Yes that is the new 200 , we had the first viewing of it via the viessman van on Friday .
I haven’t read all the comments so sorry if I have missed anything but IMO , just run it 24/7 on the viessman WC not constant temp .

The engineer as far as I am aware didn't install anything outside though as felt it unnecessary due to the Evohome?

 

[Lou]

(Just bumping a few older threads, they will drop off what is new soon)

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