High
F.73 on Vaillant ecoFIT Pure 425

Your boiler has detected that the internal sensor responsible for monitoring water pressure is sending an incorrect electrical signal, meaning the system may not be able to accurately tell how much water is inside.

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

Water pressure sensor signal in the wrong range (too low)

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.74View →

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