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Set up help for a Viessmann Vitodens 222-F, 2x heating circuits with UFH and Vitotrol 200 RF remote.

Hi from the UK,

I have had a system installed as below by a plumber who wasn't totally up to speed with Viessmann Boilers let alone the 222-F, so I have my concerns over the set up.

I have a Vitodens 222-F with weather compensation senor outside and 2nd heating circuit (H2) running my UFH, the UFH heating circuit is connected via the Viessmann 3 way Brass valve and controller. I also have a Vitotrol 200 RF which is connected to the main heating circuit H1 (Radiators) so I can control the temperature if needed from inside the house.

My concerns are:-
1. What curve settings should the main circuit H1 & the UFH circuit H2 be set to so it works correctly with each other. I know this depends on my house insulation efficiency but I need to understand how the two circuits deal with each other?
2. My Vitotrol has an internal temperature sensor, but I am told by Viessmann this does not feed this information back to the boiler and therefore has no room temperature influence on the curve etc… is this correct as the instruction manual suggests this can be turned on to communicate this info to the boiler?
3. Should the boiler by run 24/7 or use a setback temperature, at lets say 6 degrees below for sleeping times and when we are out at work?

Any help would be greatly appreciated?

Many Thanks


  • Paul Pollets
    Paul Pollets Member Posts: 3,656
    Change to the Vitotrol 300 if you want indoor feedback. Setting up the heating curves depends on the application. If you have UFH using aluminum transfer plates, a higher curve is required than having the pex embedded in lightweight or concrete. If radiators are sized for lower temps, they will have a lower curve. I typically start "staple-up" UFH at a 1.4 and see if it can keep the home warm. Sometimes the curve can be lowered. Run the (HC2) circuit 24/7. Radiators can be timed out at night because of their fast recovery. I never use more than a 5-8 degree setback. Setting the curve will depend on how the radiators were sized. Try finding a Viessmann expert. You'll need one to service and clean the system.
  • stuhelhall
    stuhelhall Member Posts: 3
    Thanks for the speedy response Paul, I guess your right, in the long term I need someone who is capapble of servicing this correctly. Its due a service in next few months so will start looking now.

    The UFH is plastic pipe which is sat in special foam pads moulded out for the pipe, these sit in between the floor joists, the floor is cermic tiled so I expect your idea to run 24/7 on the UFH makes sense, I will just need to keep an eye on the gas consumptions or would you suggest this is more economical then having a set back on the UFH?

    As for the indoor feedback I supose I was hoping to get that from what I had, the system seems to work well and I am still tweaking the curve so I expect I really dont need this added feedback, unless you suggest its worth the extra money?