Walli charger emits a loud humming or buzzing noise during operation.

Safety first: Noise alone is not always dangerous, but it can indicate loose components.

Steps:

• Localize the sound: Carefully listen to identify whether the noise comes from the contactor area, transformer, or enclosure.
• Check mounting: Ensure the Walli charger is firmly mounted to a solid surface and that all housing screws are tight.
• Internal check: With power off, open the unit and verify that the contactor and any transformers/chokes are securely fastened to their brackets.
• Measure supply voltage: Have an electrician confirm that the supply voltage is within the Walli specified range.
• Replace noisy component: If the contactor or transformer continues to buzz excessively, replace the affected component with a Walli‑approved part.