How to install a heater and thermistor on a j-head hotend


Staff member
If you need to replace the heater cartridge or thermistor on your hotend the following images and text will walk you through the process.

Lay out the parts

Start to screw in the set screw using the black hex wrench supplied with your kit. This wrench came in the clear plastic box along with the SD card and LCD screen knob

Insert the heater cartridge and tighten the set screw. Keep in mind if you have a dual extruder, the heater cartridge may have to be inserted in from the opposite side depending on which hotend it is (ie. left or right).

Take the thermistor and make sure to gently spread the two wires apart to prevent any shorts.

Place the thermistor into the little hole on the hotend keeping the wires slightly apart.

While holding the thermistor in place with one hand, start to tape the thermistor in place using 1/4" wide kapton tape. It's easier to start taping over the thermistor then wrap it around the entire brass nozzle.

Make about 3 full revolutions around the hotend and then cut off the tape. We need to save some for the next step.

Using the remaining tape, wrap it around the thermistor wires and hotend to secure them together. You only need 3 or 4 revolutions to hold in place.

And here you have it, a completed hotend with the heater cartridge and thermistor installed.