Fault code 01 shown on the display with the fault icon on: Fan is locked when inverter is off..
CauseFan fault.
Recommended fixReplace the fan.
Source:Axpert-MAX-E-TWIN-11K-Off-grid-manual-20220121.pdf· page 40Axpert-MAX-E-TWIN-11K-Off-grid-manual-20220121.pdf· page 47