Also check to see if your converter/charger is working correctly and actually going into maintenance mode. It should drop to to 13.1V when the battery is fully charged. If it is not working correctly (the WFCO units that Thor uses are not quality and I have had two that never went into maintenance mode) the converter/charger will continue to charge at 13.5v and boil off the electrolyte in you battery leading to an explosion.
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