It’s important to keep in mind that A/C units are very demanding in terms of power, and more importantly, the starting current of these machines is way beyond the running current stated in their manual. (It can be up to 5x, depending on load conditions of the compressor, temperature, etc)
Everyone is aware of the power limitations of the Grow Hub (10A resistive loads per outlet/15A resistive total), so you may think it’s safe to plug your 9A (running current) A/C machine into your Niwa Grow Hub, but that is not the case! As mentioned above, a 9A machine can draw up to 30A or more at startup, depending on the conditions. If this happens, it will fuse the soldered protection inside the Grow Hub, so the unit will not work till fixed.
To know the max amps drawn at the start and during usage of your A/C unit, you need to check the RLA/FLA information which can be found on the nameplate of the A/C, or ask the manufacturer. If you are not sure, you can assume your A/C will draw at least 3x times the running power, hence you should not control A/C units drawing more than 3A with your Grow Hub. If your A/C unit is above 3A and/or you are not sure about the max possible peak current, we recommend using the internal built-in thermostat of your A/C unit.