High Lockout
09 on Glow-worm 30ci Plus

Your boiler has lost the ability to monitor its own water pressure, meaning it has shut down to prevent damage even if there is enough water 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 fault

What causes this fault?

This fault occurs when the boiler's internal computer can no longer read the signal from the water pressure sensor. The most common reason is that the sensor itself has developed an electrical fault or has become blocked with system debris, preventing it from measuring the water level accurately.

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

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