Steam Is Emitted From The Printer Output Area - Canon LBP7018C E-Manual

Steam Is Emitted from the Printer Output Area

<Cause> Moisture in the paper evaporated due to the heat generated when the toner fixes.
(particularly when the room temperature is low).
Although this is not a malfunction, you can prevent the steam emission by replacing the paper with new
paper in an unopened package.
Solution
Also, store paper away from moisture.
"Precautions for Paper"
019A-059