[RMcNeal]

Gordon, Carl is correct. The red key removed will disconnect your batteries from the converter/charger, so don't do that.
If memory serves, your 3661 has a residential fridge (odd number at the end?).
The only breaker I turn off is the one to the residential fridge, since I don't need it running when the rig is not in use. I then prop the doors open to let it air out. I also cut off the disconnect in the battery bay that feeds the inverter to the fridge.