Softener emits a persistent humming or buzzing sound even when not regenerating.

Safety: Disconnect power before touching any electrical components.

• Isolate source: Remove the control cover and carefully listen to identify whether the hum comes from the transformer, motor, or a solenoid.
• Tighten mounts: Ensure the transformer and valves are firmly mounted to reduce vibration noise.
• Check voltage: Verify the supply voltage matches the Hansgrohe softener's rating. Overvoltage can increase hum.
• Replace noisy component: If the transformer or a solenoid continues to hum loudly and is warm to the touch, replace the affected component.