Viessmann Mechanical Vibration / Fan Imbalance

Water heater vibrates excessively or rattles when running

This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.

If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.

Possible Causes

Loose mounting screws on fan or pump, Imbalanced fan impeller, Loose casing panels, Air in system causing cavitation in pump

Safety: Turn off power before tightening or inspecting moving parts.

Tighten fixings: Check all accessible screws on the fan, pump, and mounting brackets. Tighten any loose fasteners.
Secure panels: Ensure the front cover and side panels are properly engaged and not vibrating.
Bleed air: Bleed air from the primary circuit to prevent pump cavitation.
Inspect fan: If vibration persists, the fan impeller may be damaged or imbalanced and should be replaced.

Medium 3/5

Flue Fan Assembly

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