Bill,
When not on shore power, the red light will go out when you push "store" (disconnect). When on shore power, the red light stays on when you push "store", however, the batteries are in fact disconnected.
When on shore power, you can disconnect the batteries to keep from constanly charging and all 12v systems will operate including refer and fridge. The converter supplies all 12v circuits.
Obviously, when not on shore power you must have the batteries connected.
Bob