Medium Lockout
08 on Glow-worm 30ci Plus

Your boiler has detected a problem with the sensor that monitors the temperature of its internal hot water store.

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

Micro accumulation vessel NTC fault

What causes this fault?

This fault occurs when the sensor responsible for monitoring the temperature of the small internal hot water tank fails or sends an incorrect signal to the control board. The most common reason is that the sensor has developed an electrical fault over time or the wiring connecting it to the main system has become loose or damaged.

Engineer required

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

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