Canon PC920 Service Manual page 315

CHAPTER 11 TROUBLESHOOTING
9. Others
When a machine is brought in from a cold place (e.g., warehouse) to a warm place, condensa-
tion can occur inside it, leading to various problems; e.g.,
a. Condensation on the scanner (glass, lens, mirror, reflecting plate) will cause dark images.
b. The drum is likely to be cold (high OPC electrical resistance), not enabling good contrast.
c. Condensation in the pickup/feeding assembly tends to cause feeding faults.
d. Condensation on the lower roller of the manual feed assembly will reduce friction, causing
pickup faults.
If condensation is noted, dry wipe the parts in question.
The cartridge can develop condensation if it is opened immediately after it has been brought
from a cold to warm place. Instruct the user so that the cartridge is not opened before it has become
used to the room temperature (one to two hours).
11-50
COPYRIGHT © 1999 CANON INC. CANON PC800s/900s REV.0 AUG. 1999 PRINTED IN JAPAN (IMPRIME AU JAPON)