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10kW Viessmann Vitocal 200-A with Vitocal 222-A
Good Morning All
After following the threads on this site, I feel I need to introduce myself and provide a summary of my system.
We moved into a new barn conversion in 2022, the majority of the work was completed by myself and my wife, employing trades as required. The build was effectively a new skin inside the old barn, all on one floor, of 195sq meters, underfloor heating throughout. Because of this we knew exactly how much insulation was in the property and the U values of all the windows and doors. Theoretically this should of given us an accurate energy performance figure to size the air source heat pump. We have a 10Kw Viessmann Vitocal 200-A external unit, with a Vitocal 222-A Indoor Unit with integrated 220L DHW cylinder. As we installed all the insulation and took great care in making it to the best we could, and to a higher standard than most builders, the pump is slightly oversized for the property, this doesn’t seem to be a problem with the Viessmann unit, and it modulates its output down to about 25% capacity very easily. Coupling the heat pump with the underfloor heating, and a low loss property, means we can run it at low temperatures, current WC slope has 27° @ +10, 30° @ 0 and 32° at -10.
We used our Local plumber to do the install, he was keen to start fitting heat pumps even though this was his first, we were very happy with his work using his plumbing experience has avoided some of the problems others have had. Because he hadn’t fitted any before I agreed to set up all the WC etc. and feed back to him my findings. At some point in the future I will post my experiences with this.
Welcome to the forums @mikef – how is your system holding up? You please with it so far?
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