Alternator will initially charge at 14.6+ volts and as it heats up with the rest of the engine will drop into the 13.8 to 14.2 zone. This is great for the chassis battery but the house battery is often connected through a relatively long wire isolator etc that will drop voltage a bit and provide a slower charge.
You can get an aftermarket regulator that does a specific 3-stage charging routine. More popular in the boating world.
Not sure how much off-grid camping you do but also consider 100 to 300 watts of solar instead of the converter upgrade. No more worry about plugging in.
