You can add a small device called a Trik-L-Start charger that will use the house battery to keep the chassis battery charged. Obviously it would not be especially helpful if you are not keeping your house batteries charged but it’s easier than using multiple chargers and worrying about it. I added it when I put my solar maintainer on my house batteries. Now my small solar system is able to keep all of my batteries ready to go even in long storage.
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