In my 2014 Hurricane 34E a 12V Fantastic Fan Endless Breeze fan lives virtually permanently right in the middle of my dash board circulating air.
It's been plugged in to the top socket right next to the steering wheel for over a year.
I notice that the speed of the fan gently fluctuates as the voltage converter/battery charger normally cycles and does it's thing, (you can hear it's quiet fan go on and off).
So, I'm venturing to say that the 12V sockets on the dash are connected to the house batteries, (which are definitely connected to the voltage converter/charger).
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