Machine emits unusual odors (musty, sour, or rancid) during brewing or steaming.

Safety first: Unplug the machine before deep cleaning.

Step-by-step checks:

• Clean brew group: Rinse thoroughly and allow to dry daily.
• Wash drip tray and dreg drawer: Clean with warm soapy water and dry completely.
• Refresh water: Empty and refill the water tank daily with fresh water.
• Clean milk system: Run the milk cleaning program and disassemble and wash all milk components.

When to call a technician: Persistent odors after thorough cleaning may indicate internal contamination and require professional disassembly and cleaning.