I have read that the vehicle alternator will charge the vehicle battery but also the house batteries while driving, how can I check if my RV is doing that also? I checked the manuals left by the previous owner no info, 2013 Chateau 24ft on a Chevy 3500
1 - Obtain a Digital Multimeter (DMM)
2 - learn how to use said DMM
3 - Unplug the RV from SP for at least an hour but leave the interior lights on
4 - Start the RV engine
5 - After running the engine for 5 minutes, and while it is still running, measure the voltage of your house batteries
If greater than 13.5 VDC the alternator is charging the house batteries.
Do you have a meter near them that shows how many volts they've got left in them?
If you do: take a look at it without the engine running, and then try it with the engine doing it's thing...
(Give about five minutes or so between readings...)
If it's working: You'll see the difference on that meter.