Machine shows E02 and stops brewing or rinsing

Safety first: Unplug the coffee maker and let it cool for at least 30 minutes. The boiler/thermoblock can remain hot for a long time.

Basic user checks:

• Power reset: Disconnect power for 5 minutes, then plug back in and restart. Sometimes transient sensor errors clear after a full reset.
• Descale: If the machine has not been descaled recently, run a complete descaling cycle with Gaggia descaler. Heavy scale can cause localized overheating and trigger sensor faults.

Internal inspection (for experienced users):

• Remove the top/side cover to access the boiler or thermoblock assembly.
• Locate the NTC sensor (usually a small probe or disc attached to the boiler with two wires).
• Check connections: Ensure the NTC plug is fully seated on the main board and that the wires are not broken or burned.
• If you have a multimeter, measure the NTC resistance at room temperature and compare with Gaggia specifications (typically in the tens of kΩ). A reading of open circuit or 0 Ω indicates a failed sensor.

If wiring and descaling do not resolve E02, replace the NTC sensor. If a new sensor does not fix the issue, the main control board may be defective and should be replaced by a technician.