The advantage of the dual boiler is that the brewing boiler and steam boiler are separate. This allows you to operate the steam boiler at a higher temperature (and pressure) without having a negative impact on the brewing process.
Up to 2 bar pressure can be set via the web interface - almost 70% more than usual. This allows you to foam significantly more and, above all, faster.
In addition, the steam boiler is quite large and the water to steam ratio is designed in favour of sufficient space for steam. More than half of the volume is available for steam at the Xenia.
The heat loss during operation was additionally reduced by a 10mm thick insulation made of needle felt and an overlying stainless steel sleeve.
Related Links:
https://www.kaffee-netz.de/threads/xenia-erfahrungsaustausch-und-wartezimmer.103770/page-240#post-2218121
https://www.kaffee-netz.de/threads/xenia-erfahrungsaustausch-und-wartezimmer.103770/page-238#post-2215292
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