Solder waste accumulates in the waste collector each time the tip is cleaned. Therefore, it has to be removed and disposed from time to time. The sensor cover, which is located near the opening also has to be cleaned. Here's how:
Cleaning The Waste Collector

Step 1: Pull out the AC adaptor plug from the unit and remove the cover.
Step 2: Remove the solder waste collector and clear the stacked solder using a plastic spatula.
Step 3: Dispose the solder waste and return the waste collector to the unit.
Step 4: Clean the sensor with a soft brush.
Step 5: Return the cover to the unit and insert the AC adaptor plug.
Cleaning The Sensor Cover

Step 1: Remove the AC adapter plug from the unit and detach the sensor cover.
Step 2: Wipe off the dirt using a cloth dampened with alcohol.
Step 3: After cleaning, return the sensor cover to its original position and insert the AC adapter plug into the unit.
**Replace the sensor cover if dirt cannot be removed, or if the cover is broken or damaged
Cleaning the waste collector and sensor cover regularly ensures that your Hakko FT-720 Tip Cleaner remains in optimal condition. By keeping these components free from debris, you help maintain the efficiency of the rotating brushes and sensor.