How to clean the fan and the heatsink?

You can safely clean your MateBook D15’s fan and heatsink without fully opening it by using short bursts of compressed air through the vents while the laptop is powered off and unplugged. Gently blow air into the exhaust and intake vents, tilting the laptop so dust can fall out, and avoid spinning the fan too fast by holding it still with a small stick. This helps clear surface dust, but to replace the thermal paste or deeply clean the heatsink, you’ll need to remove the bottom cover and disconnect the fan. It is something best done carefully or by a technician if you’re unsure.