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I am renovating my 4 bed Victorian house with solid walls.

We are about to replace the boiler and I am looking at a Worchester bosh 36kw cdi compact with WF100 weather compensator. I also want to take the opportunity to zone the upstairs and downstairs separately as the flow and return for upstairs are very close to where the new boiler will go.

I chose the 36cdi as it has a hight flow rate for the HW and is compact enough to fit in a cupboard.

My total heating output from my radiators is ~ 7kW downstairs and ~7kW upstairs. The Minimum heat output for the 36cdi in non-condensing mode is 7.0 but i cant find figures for minimum output in condensing mode: 1. What would the minimum output be in condensing mode? 2. Does the fact that the minimum output is slightly higher than the rad output of a zone mean that the boiler will never go into condensing mode with only 1 zone open? 3. Does this mean i should choose between zoning and weather compensation? 4. In my position would you go for zoning, weather compensation, or both? 5. Would you have internal thermostats as well?

Thnaks so much for your help in advance!

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