I have a 16,000 BTU AC 120v/ 13.5amp in my medium size boat. I have installed it to the AC2 output on the MultiPlus 12/3000/120. With shore power connected 120/30 amps The AirCon fan comes on, as the condenser clicks to start all power is lost Multiplus literally shuts down. Sometimes it resets other times it does not. If I switch Multi off for 5 seconds and back on Multi goes into bulk charging mode and appears to run fine, until Air Con tries to start again. Very bad when boat is unattended. I've hove gotten low battery lights, overload lights, and both low battery and overload lights lit at the same time.