Mr. Coffee ROASTBOY User Manual & Warranty page 7

When you press the start button, a pop-up of "Empty the Chaff Drawer" will appear.
Take out the Chaff bin, empty it and replace it back in the drawer
and the preheating stage will begin.
2. Once the company logo (ex. Mr. Coffee) is selected,
the RoastBoy interface will appear on the screen.
Empty the Chaff Bin and the preheating stage will begin.
The voice instruction will inform you that it is now in the "preheating stage"
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