High Lockout
09 on Glow-worm Ci Range

Your boiler has lost track of the system's water pressure because a sensing part has stopped working properly.

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 how much water is inside the system, causing it to shut down for safety. The most common reason is that the pressure sensor has become blocked with system debris or its electronic internal components have simply failed over time.

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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