To clean dust out of a portable heater:
1. Unplug the heater and allow it to cool down completely.
2. Use a soft cloth or brush to gently remove dust from the exterior.
3. Use a vacuum cleaner with a brush attachment to clean the vents and grills.
4. Check the manufacturer's instructions for any specific cleaning recommendations.
5. Plug the heater back in and ensure it is functioning properly before use.