They are on the Axis and Vegas. The USE/STORE switch must be in the USE position though. They charge the house batteries through the Battery Control Center (BCC) or the Trombetta/BIRD depending on how the Vega/Axis is configured.
I'd be surprised if the ACE is not similarly configured. Do you have the electrical wiring diagrams for your VIN from Thor customer service? If not you should go to the Owners section of the Thor Motorhome website. Here is the link to their Customer Care site. While you are asking for the electrical drawings, ask them for the fresh water, waste water, and dash harnesses as well.