Display shows "Hi" and the vacuum refuses to charge or run after heavy use.

Safety first: Remove the battery pack and place the vacuum and battery in a cool, dry room away from direct sunlight.

Allow to cool:

• Leave the battery and vacuum to cool for at least 1 hour.
• Do not place in a fridge or freezer; rapid cooling can cause condensation.

Check airflow components:

• Clean filters and clear any blockages in the floorhead, wand, and cyclone to reduce motor load.

Once cooled and cleaned, refit the battery and test again. If "Hi" appears even when the unit is cold, the temperature sensor or control PCB may be faulty and require professional replacement.