Battery select switch question

[Marsea5]

Hello all
My new to me '01 28TE battery selector switch 1(start) / off / 2 (house)

All of my previous boats have had the all / parallel choice as well. I would run on "all" so both house and start gets a charge then switch to just house when on the hook.

So my question or assumption is the motor is always charging the start bank and I should run on house selection for charging underway? I'm also assuming like in the past, never switch banks while underway unless you have a switch with automatic field disconnect so as to not damage alternator. Looks like my switch does not have afd.
Thanks!

[AlbinOhhh]

I think it’s impossible to know how your boat is actually wired. Your best bet is a voltmeter to check if a charge is actually going to the batteries in various configurations.