The information in this article applies to UltiMaker S series printers, including the UltiMaker S3, S5, S6, S7, and S8.
Tip: The nozzle covers for the UltiMaker 3 (newer-style) and Factor 4 are very similar, but they use a different part. See the following articles for checking and replacement instructions for these printers: UltiMaker 3 - Check the nozzle cover or Factor 4 - Check the nozzle cover.
The nozzle cover shields the print cores from cold airflow from the fans, which helps the print cores to maintain a stable temperature while printing. The cover also helps to prevent backflow of material into the print head when something goes wrong during printing.
The heat of the nozzles may cause wear on the nozzle cover over time. It is recommended to check the quality of the cover at least once every three months. This may be necessary more frequently when printing with high-temperature materials. The accessory boxes of the UltiMaker S series printers contain three spare nozzle covers.
Note: When using a CC, CC+, or DD print core, it is recommended to check the quality of the nozzle cover once every month. More information about maintenance actions when using these print cores can be found here: The CC print core maintenance and The DD print core maintenance
Checking instructions
Caution: Make sure that the print cores have completely cooled down before starting this maintenance action. Turn off the printer or ensure it is disabled in the UltiMaker Digital Factory to prevent new print jobs from starting remotely.
Examine the bottom of the print head to see if the holes where the nozzles come through are still round and if the cover still forms a good seal. Also gently open the fan bracket to check the other side of the silicone nozzle cover.
If the nozzle cover looks burnt, frayed, or damaged, it is recommended to replace it. Follow the instructions below.
Note: Never start a print if the nozzle cover is not installed. This can cause errors such as ER31 or it can lead to backflow of material into the print head (Flooded print head).
Replacing the nozzle cover
Caution: Make sure that the print cores have completely cooled down before starting this maintenance action. Turn off the printer or ensure it is disabled in the UltiMaker Digital Factory to prevent new print jobs from starting remotely.
The nozzle cover provides a good seal, but it is a little complicated to install. Watch the video below for step-by-step instructions. Alternatively, follow the detailed instructions on this page:
Replace the S series nozzle cover
