Sealing issues on the SendPro C Lite, SendPro C, SendPro+

Position envelopes correctly and ensure the moistener tank has enough E-Z Seal® to prevent sealing issues.
Products affected: SendPro® C Lite, SendPro® C, SendPro®+  (2H00, 8H00)


The device is not sealing or only partially sealing envelopes.


There may be inadequate sealant in the moistener tank, or there may be an issue with the wick or brush in the moistener.


  1. Be sure to slide the envelope flap under the edge of the feed deck. Otherwise, the moistener cannot wet the flap.
    Envelope flap fed underneath the feed deck
  2. Check the sealant level by looking at the sight glass on the left side of the moistener tank.
    Moistener tank sight window
  3. If the sealant level is low, add E-Z Seal® until it reaches the bottom of the fill hole. Do not overfill the moistener tank.
    • If the tank was empty, allow 30 minutes for the moistener brush and wick to get completely wet before trying to use the moistener.
  4. Check if the moistener brush is dry. If it is:
    • Make sure that the white thumbscrews on the bottom of the sealer are tight.
    • Try wetting the moistener brush manually.
    • Make sure that the brush is contacting the wick. Lift the wick up slightly so that it contacts the brush.
    • If the brush dries out quickly, replace the moistener wick*.
  5. Check if the moistener brush is dirty. If it is, remove the moistener brush, clean it in plain water, and rinse thoroughly. If the brush will not rinse clean, replace the moistener brush.
  6. Replace a worn-out moistener brush*.

*​You can order a Moistener Replacement Kit (#946-1) from the supply line, which includes a wick, shield, and brush assembly.

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UPDATED: January 04, 2024