Machine shows A5 and will not heat or brew; sometimes accompanied by a cold water output.

Safety first: Unplug the machine and allow at least 30–45 minutes for internal components to cool. Risk of burns and electric shock.

Step 1 – Power reset

• Unplug the machine for 10 minutes to allow any thermal protection to reset.
• Plug back in and test. If A5 reappears immediately, proceed to further checks.

Step 2 – Descale to improve heat transfer

• Fill the tank with descaling solution according to Lavazza instructions.
• Run the descaling program or repeated hot-water cycles.
• Allow the solution to sit in the thermoblock for 10 minutes, then flush thoroughly with clean water.

Step 3 – Inspect thermoblock and sensors (advanced)

• Unplug the machine and remove the cover.
• Locate the thermoblock (metal heating block with water tubes and electrical connections).
• Identify the NTC temperature sensor (small probe or sensor clipped to the thermoblock) and any thermal fuses/thermostats attached.
• Check for loose or corroded connectors; reseat them.
• Visually inspect for burn marks or cracked insulation.

Step 4 – Component replacement (for technicians)

• If the NTC sensor is open/shorted (requires multimeter), replace it with the correct Lavazza-compatible part.
• If a thermal fuse has blown, investigate cause (scale, blocked pump, control fault) before replacing.
• Do not bypass thermal safety devices; this is dangerous.

When to seek service

• If you are not trained in electrical diagnostics, contact a professional for thermoblock or sensor replacement.
• Persistent A5 after descaling and connector checks usually indicates a failed sensor or control board.