I have a 9kw solar array and a series 2 powerwall currently installed. As I understand it, the house is completely backed up via the powerwall. I have confirmed this and everything seems to work as expected.
However, there is one thing I don't understand. I have one circuit that remains outside the backed up circuit, a hot tub. Whenever the hot tub clicks on I can see a large 6kw power draw from the grid (which makes sense) and from the powerwall. It is this draw from the powerwall I don't understand. If the hot tub is not part of the backed up circuit I would have expected it to be completely powered from the grid and not consume any solar or powerwall resources. Anyone understand what is happening there?