The PT100 sensor measures the temperature in the hot end. It provides fast and accurate feedback about the current temperature, ensuring optimal print quality.
If the PT100 is damaged, the Ultimaker 2+ may show the error message "Error - Stopped Temp Sensor". If this error appears, it is recommended to follow the troubleshooting steps described on this page. If this does not help, then the sensor will need to be replaced.
To replace the PT100 sensor, it first has to be taken out of the print head and disconnected from the mainboard. The following steps describe how to correctly replace the PT100 sensor:
- 1x 2288 PT100 sensor
- 2.0 hex screwdriver
- Phillips screwdriver
- Blue tape
- 20 minutes
1. Remove the clamp clip
- Place the print head in the front-right corner.
- Use your fingernail to remove the blue clamp clip.
2. Remove the Bowden tube
- Press down on the white tube coupling collet.
- At the same time, pull the Bowden tube upwards, out of the print head.
3. Remove the thumb screws
- Now put the print head in the middle of the printer for easier access.
- Loosen the four thumb screws and take them out of the print head.
- Put some tape around the three parts of the print head housing. This ensures that the parts stay together.
4. Remove the fan bracket
- The fan bracket is attached with two M3x4 bolts on either side of the hot end.
- Use the hex screwdriver to remove all four bolts.
5. Remove the sensor from the heater block
- Use a Phillips screwdriver to loosen the set screw on the bottom of the heater block.
- Pull the sensor out of the opening on the right side of the heater block, as seen from the back.
6. Put the printer on its side
- Manually move the Z stage all the way to the top.
- Gently place the Ultimaker 2+ on its right side.
7. Loosen the mainboard cover
- Loosen the two M3x12 bolts that attach the mainboard cover from the inside of the printer, while holding the lock nuts in place with pliers or a socket wrench.
8. Remove the mainboard cover
- Pull the front of the cover away from the bottom panel.
- Slide the mainboard cover towards the front of the printer.
9. Disconnect the sensor
- Remove the sensor from ‘TEMP1’ on the mainboard.
10. Pull out the sensor
- Firmly hold the braided sleeve with one hand.
- With the other, take the end of the sensor at the electronics and pull it out through the braided sleeve.
1. Connect the new sensor
- Connect the new PT100 sensor to ‘TEMP1’ on the mainboard.
2. Insert the sensor into the braided sleeve
- Thread the other end of the sensor through the hole in the corner of the bottom panel.
- Push the sensor through the shrink sleeve, into the braided sleeve.
✔ Tip: If you can’t access the end of the braided sleeve, you may need to remove the left motor cover. It is attached with two M3x10 bolts; one in the top of the left panel and one in the bottom of the back panel. Remove these bolts and take the motor cover out of the printer.
3. Forward the wires through the braided sleeve
- Push the sensor into the braided sleeve as far as possible.
- If the wires can’t be pushed any further, locate the metal end of the sensor inside the sleeve and pull it forward.
- Alternate between pushing and pulling if necessary, until the metal end of the sensor exits the print head.
4. Insert the sensor into the heater block
- Push the metal end of the sensor into the opening on the right side of the heater block, as seen from the back.
- Make sure the open side of the metal cuff is facing down.
- Use a Phillips screwdriver to tighten the set screw at the bottom of the heater block to secure the sensor.
✔ Tip: Before tightening the set screw, make sure that the heater cartridge is still fully inserted. After tightening, gently pull at the heater and sensor to check that they are secure.
5. Put the mainboard cover back in place
- Slide the cover over the board at a slight angle and insert the two small tabs in the back panel. Make sure that no cables are stuck between the cover and the frame.
- Put the cover against the bottom panel, making sure that the two small tabs in the middle are inserted into the notches in the bottom panel and left panel.
6. Secure the mainboard cover
- Insert the two M3x12 bolts through the bottom panel from the inside of the printer.
- Hold the lock nuts in place with pliers or a socket wrench and tighten the two M3x12 bolts.
7. Place the printer upright
- Turn the Ultimaker 2+ upright again.
- Manually move the Z stage all the way down.
8. Attach the fan bracket to the hot end
- Align the fan bracket with the hot end.
- Secure the fan bracket to the hot end with the four M3x4 bolts.
✔ Tip: To ensure that the nozzle is precisely in the middle of the hole in the fan bracket, first only loosely secure each of the four bolts. Look at the bottom of the print head to align the nozzle, then tighten the four bolts fully.
⚠ Caution: If the nozzle touches the sides of the hole in the fan bracket, the heat will conduct throughout the bracket. This will make it harder for the Ultimaker 2+ to maintain its temperature during printing, which can lead to error messages and performance issues.
9. Align the print head housing and the hot end
- Remove the tape from the print head housing.
- Move the hot end upwards to align it with the housing parts.
10. Attach the print head housing to the hot end
- Insert the four thumb screws.
- Screw them into the bottom aluminum plate, but do not tighten them all the way.
✔ Tip: Make sure that all cables run neatly side by side and the fan wires are not behind the back two thumb screws.
11. Tighten the thumb screws
- Completely tighten the two thumb screws at the back by hand.
- To tighten the front two thumb screws, use a calibration spacer. Place the tool in between the aluminum plates of the hot end.
- Tighten the front two thumb screws until the spacer fits securely between the plates, but can still easily be removed.
⚠ Caution: The print head alignment aid is very important to set the correct pressure on the hot end. Securing the print head too loosely may lead to leakages, while overtightening the thumb screws will decrease the lifespan of the TFM coupler.
12. Insert the Bowden tube
- Press down on the tube coupling collet in the print head.
- Push the Bowden tube all the way in.
13. Ensure the Bowden tube is correctly inserted
- Let go of the tube coupling collet and gently pull the Bowden tube, along with the tube coupling collet, approximately 2 mm upwards.
- Hold the tube coupling collet up with your fingernail.
- While holding the tube coupling collet up, push the Bowden tube down again.
14. Secure the clamp clip
- Place the blue clamp clip around the tube coupling collet to secure the Bowden tube.
Note: If you removed the left motor cover earlier, don’t forget to put it back in place. Click the cover’s tabs into the bottom panel and secure the cover in place with the two M3x10 bolts.