Here is a link to the schematic for the BCC (Battery Control Center)
http://tinyurl.com/6gfbdt
I have had the same problems... The converter simply does not put out enough to charge the system. I added the Charge Wizard and that helped. The Charge Wizard (about $30 at CW) plugs into your 9155 converter and helps charge the batteries. If you have a dead cell in a battery it will never charge up.. that was my problem. There are several drains on the batteries even with the Battery Disconnect trigered... all of the monitors like LP, Carbon Monoxide, plus the Climate Control Center.
ps... BCC is now up to Rev. N