Lelit Mara X: Cleaning the Temperature Sensors

If the boiler in your Mara X fails to maintain a consistent temperature or pressure, the culprit could be a dirty sensor. This guide demonstrates how to clean and re-seal the temperature sensor.

Tools Needed:
- 17mm crescent wrench
- Scouring pad or steel wool or wire bristle brush

NOTE: The machine should be unplugged and cool to the touch before you begin.

1. Start by removing the panels from the machine.

2. If necessary, create room to work by removing the reservoir tray and setting it aside.

3. Identify the steam mode temperature sensor installed in the machine's boiler. 

4. Trace the double red wire to where it connects on the other side of the boiler, then disconnect it.



5. Use the 17mm wrench to unscrew the temperature sensor.
(If you need more room to work, follow Steps 4 and 5 in this guide: Lelit Mara X: Cleaning the Fill Probe)

6. Clean any build up up from the top of the boiler and the temperature sensor threads.

7. Use the method of your choice to clear the build up from the temperature sensor.
(Remember even a tiny bit of build up can cause problems, take your time and be thorough.)


8. Before re-installing the temperature sensor, wrap the threads in a few layers of PTFE tape.

9. To clean the machine's coffee mode temperature installed in the heat exchanger, first follow this guide for gaining access to the underside of the machine:
Lelit Mara X: Accessing the Underside of the Machine

10. Identify the coffee mode temperature sensor and follow the same steps to unplug and unscrew it, then clean the sensor. Don't forget to seal the threads with Teflon tape before reinstalling.