High
F.75 on Vaillant ecoFIT Pure 830

Your boiler is struggling to detect the movement of water, which usually means it cannot confirm the pump is working properly and has safely shut down to prevent damage.

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

Fault: No pressure change detected when starting the pump

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 →

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