Albro359-I will not disagree that you had a problem that was "fixed" by removal
of the ACR, but think about the physics involved. Your house bank was being charged by a three step regulator
and it was in bulk mode ramping up to the acceptance charge voltage knee. The alternator is putting out almost as much current (mechanical load) as it can. When the ACR senses 13.6 VDC for 30 seconds or 13.0 VDC for 2 minutes it combines the starting battery. If
the starting battery has only been used to start the engine
, then it may have 1 amp-hr discharged out of it. If the starting battery also powers other equipment
(windlass, bow thruster, etc.), then the scenario changes.
It is my opinion that you had something else going on that caused all hell to break loose as the addition an electrical
load as low as that represented by the starting battery was not the cause.