15% or so is seen after a few weeks, wish I used it more often thus not having to worry about it discharging. Too many other things going on. The 500 to 700ma parasitic draw and the play time in the rig with the stereo on consumes much of the power.
I found my engine battery which supplies power to the entry steps even when the disconnect is opened discharges faster than the house batteries. The starting battery SOC drives my recharge cycle.
Have you considered lowering the float voltage to say 13.2 with temp compensation? During the winter my rig is in a heated barn and pluuged into shore power where the modified converter supplies 13.2 24/7 for 4 or 5 months.
