Low
S.22 on Vaillant ecoTEC Pro 30

Your boiler is simply preparing to deliver hot water by briefly running the internal water pump before lighting the burner.

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

Technical description

DHW mode: Pump pre-run

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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