... preheating chassis work; pressing the blue button on the front panel (up key), the red button (down key), can be within 0-450 °C ... and user experience of their own set different preheat temperatures.3. Machine tuning and adjustment:Infrared preheating chassis of the ... preheating chassis clean, regular use of anhydrous alcohol to clean!3. Careful, high temperature operation, safety, to prevent burns.4. ...