High
F.73 on Glow-worm 38cxi

Your boiler's internal sensor that monitors water levels is unable to send a reading to the control board, preventing the system from running 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

Water pressure sensor not connected or has short-circuited

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.75View →F.22View →F.24View →

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