I had a 1,000 watt. It burned out the start circuit on the fridge in a few weeks.
Then I got an 1,800 watt. That worked fine.
But I had to shut off the fridge when I started the truck or risked causing too low voltage for the inverter if the fridge happened to try and start at the same time.
Now have a pure sine wave 2,500 watt inverter and the Maxwell Engine Start Module, never have a problem.