Safety first: Unplug the unit and let it cool. Hot water may still be inside the system.

Check reservoir seating: Remove and reseat the water reservoir, ensuring it clicks or sits firmly in place. Clean the inlet screen at the base of the reservoir if present.
Prime the pump: Fill the reservoir to the MAX line. With the machine unplugged, gently tap the side of the unit near the pump area (usually behind or below the reservoir) to dislodge air bubbles. Plug in and start a brew with no coffee to see if flow resumes.
Descale: Run a descale cycle to clear any mineral deposits in the flow meter or pump lines.
Listen for pump noise: During a brew attempt, listen for a humming or clicking sound from the pump. No sound suggests a failed pump or electrical issue.
Service required: If ERR3 persists and there is no water flow, the flow meter or pump likely needs replacement. This involves opening the unit and working with pressurized hot‑water components; seek professional service.

Display shows “ERR3” and the machine may not heat water or may stop mid‑brew.

Possible Causes