USMC3531

Just picked a 2013 280SC and wasn't sure on the battery switches. I have three batteries 2 for the start and one for the house. looks like the house battery isn't charging when the battery switch is in the off position. Not sure if the start batteries are charging in the off position either, they are brand new AGM so they are still pretty strong and they start the boat with ease. I'm plugged in to shore power and the battery charger is working. Do the battery switches need to be on for the batteries to charge?