Lelit Mara X: Cleaning the Fill Probe

If the boiler in your Mara X over-pressurizes or the pump runs until the boiler overflows, the culprit could be a dirty fill probe. Even a tiny bit of build-up can prevent the probe from accurately reading the water level in the boiler.

Tools Needed:
- 19mm deep socket and ratcheting wrench
- 14mm deep socket
- 17mm open-ended wrench
- PTFE tape aka Teflon plumber's tape
- Scouring pad or steel wool or wire bristle brush

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

1. Start by removing the panels from the machine.

2. Create room to work by removing the reservoir tray and setting it aside.

3. Identify the fill probe.

4. Next, we'll need to create room to access the fill probe by disconnecting the steam delivery tube. Use the 17mm wrench to unscrew the compression fittings at both ends of the steam delivery tube.

5. Use the 14mm socket to unscrew the adapter fitting in the boiler.

6. Unplug the fill probe wire.


7. Use the 19mm socket to unscrew the fill probe assembly from the boiler.


8. Use the scouring pad or wire brush to clean the exposed tip of the fill probe. Even a tiny bit of debris or hard water build up can prevent the fill probe from accurately sensing the water level in the boiler.

9. Before reassembly, wrap the fill probe threads in a few layers of Teflon tape.

10. Follow these instructions in reverse to reassemble the machine. Don't forget to add Teflon tape to the brass adapter that connects the steam delivery tube to the boiler.

NOTE: It's important to drain the machine's boiler before next operation to prevent a recurring over-filling or over-pressurizing problem:
Lelit Mara X: Draining the Machine