Medium Lockout
F7 on Glow-worm 30ci Plus

Your boiler's hot water sensor has failed or disconnected, meaning the system can no longer tell how hot the water is.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

Technical description

Domestic hot water NTC fault

What causes this fault?

This fault occurs when the sensor responsible for measuring the temperature of your tap water fails or loses its electrical connection. Over time, these sensors can degrade due to constant heating and cooling cycles, or the internal wiring may corrode, preventing the boiler from knowing when to stop heating the water.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

F1View →F2View →F14View →

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