We wind up with 15/20 amp several times per year. To make it work for us the batteries must be charged as the Magnum will kick out over 100 amps and with the fridge and inverter that can trip a 15 amp. Starting with charged batteries we never have any issues at all and luckily mine don't trip the GFCI either.
During the cooler months all we need it heat and the Aquahot handles that well along with the hot water. We don't use the 120v element in the Aquahot however.
__________________
|