Service manual

ENWW Chapter 7 Troubleshooting 221
Envelopes
Because of the variety of folds and cuts available, it is difficult to specify the types of envelopes
that perform well with HP LaserJet printers. It is very important to test a sample envelope before
purchasing a large quantity. The specifications for media also apply to envelopes. Avoid
envelopes that contain contact adhesives.
Following are a few recommendations for feeding envelopes:
● Closely inspect the leading edge of the envelopes before feeding them into the printer. Verify
the leading edge is flat. Watch for envelope curl and loose folds. If necessary, flatten the
leading edge of the envelope before feeding.
● Be patient! In manual-feed mode, the printer displays a message when prepared to accept
the next envelope. Always wait for this message to appear before loading or feeding
envelopes into the printer.
● Do not allow a large quantity of envelopes to accumulate in the output tray. If too many
envelopes accumulate, they can interfere with the output path.
● Use the rear output tray when printing envelopes.
The main causes of problems with envelopes on HP LaserJet printers are:
● folds (two or more thicknesses of paper)
● edge creases (sharp or rounded)
● glued edges (sealing when fused)
● uneven printing surfaces
For fewer problems, follow these guidelines:
● Corner folds must be well-creased, and contain no more than two thicknesses of paper.
● Envelopes must lie flat.
● Paper grain should be diagonal.
● Adhesives must meet HP specifications for fusing compatibility.
● Basis weight must not exceed 11 kg (28 lb).
● Under no circumstances should envelopes have clasps, snaps, or windows, or use synthetic
materials. Severe damage to the printer can result.
Table 26. Envelope construction
Good construction Poor construction