Canon BJC-250 - Manual (Page 49)

Printer Guidelines
Follow these guidelines to avoid damage to your printer and harm to you or others:
Set the printer on a stable surface. Do not use an angled printer stand. Avoid setting
the printer in direct sunlight.
Keep the front cover closed when printing.
Do not set anything on top of the printer
Make sure the power is off any time you connect or disconnect the AC adapter or
interface cable.
Do not unplug the AC adapter unnecessarily.
Do not unplug the printer or turn off a power strip to which the printer is attached
when the printer's power is turned on. This may prevent the print head unit from
returning to the home position on the right and being capped, which may cause the
print head to dry out. This is critical. If left uncapped, the print head unit may clog
and may need to be replaced.
Do not move the mechanism that holds the BJ cartridge. Attempting to move the
BJ cartridge holder may damage delicate mechanical parts.