High Lockout
F.11 on Glow-worm Energy System

Your boiler has detected an electrical fault with the internal sensor that monitors the temperature of the water used for your heating, causing the system to shut down for safety.

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

Flow temperature sensor short circuit

What causes this fault?

This fault occurs when the boiler's internal computer receives an electrical signal suggesting the temperature sensor has malfunctioned or 'short-circuited'. The most common reason is that the sensor itself has failed internally, but it can also be caused by water leaking onto the electrical connections or a damaged wire touching the boiler's metal casing.

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.10View →F.22View →F.73View →

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