High
S.54 on Vaillant ecoTEC Pro 30

Your boiler has temporarily paused to protect itself because the water pressure inside the system is currently too low to run safely.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Product is within the waiting period of the operation blocking function as a result of low water pressure (temperature gradient)

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

F.22View →F.73View →F.75View →

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