Bill,
Not sure how old the house batteries are as we purchased the RV last fall and I am not able to find a date stamp, I am sure they are over 5 years though.
I checked last night and the panel that shows voltage was flashing overload, it turned the switch on the panel off and then on and the overload indicator light stopped flashing.
We have a mechanic working on the issue and I am reaching out to him to give him the recommendations I am collecting from all who reply to this thread. See the attached photos from last night.
Thank you your input.
Carl