The electrical demands have been quite insignificant, just a bit of lighting as we come in as sun is setting. I'd check the volt meter quite regularly but didn't record... I recall past few weeks being in the 11V range... and yesterday wasn't even on - embarrassed to confess that it appears I completely drained the battery. Cabin (non LED) lights would glow dim, but the LED nav lights wouldn't come on... so I switched battery switch to 'combine' and that did the trick. For my setup, is the ACR not supposed charge the house once the starter battery has reached 13V+? It was a 2.5 hour 8 knot cruise yesterday at 3000 RPM from 81A alternator. I am puzzled as to why it not charging the house. I plugged in once we were back yesterday... so read a full charge on the monitor today.
Based on your info, it seems that perhaps one of the fuses linked to the ACR has blown. The ACR fuses will be located on engine and house battery. Look at the side of the fuse and you’ll probably see a broken link in the fuse. Replace with the same thing.