Setting the fan heater to 1000 W is not possible, as there are only two power settings available: 1200 W and 2000 W. There is no 1000 W power level on this model.
You can choose between the two available heating levels (1200 W or 2000 W) via the controls on the device or via the Philips Air+ app for remote control and the automatic mode based on artificial intelligence that optimises energy consumption, but there is no 1000 W setting.