The ability of DELTA Max to run the devices and the duration of running the devices depends on the specifications (wattage/voltage/current) of the air conditioning unit and the fridge.
We have tested DELTA Max on a 60W mini-fridge (car fridge) and it was able to run for 33hrs using DC output ports. We have also tested it on a 120W fridge, and it was able to run for 14hrs using AC output ports. And we also used DELTA Max to run a 1800W air conditioner using AC output, and DELTA Max managed to run it for 1 hour.
You can contact our customer support on this contact us and provide them with the specifications of the devices you want to power, and they will help you check if DELTA Max is compatible with the devices and your needs.