Medium Lockout
F07 on Glow-worm Ci Plus

Your boiler's hot water sensor has developed a fault, meaning it cannot accurately measure the temperature of the water coming out of your taps.

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 monitoring your tap water temperature fails or begins sending incorrect electrical signals to the main control board. The most common reason is natural wear and tear or internal corrosion of the sensor's probe, which prevents the boiler from knowing how hot the water is. In some cases, the error can also be triggered by loose or damaged wiring connecting the sensor to the boiler's computer.

Engineer required

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

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Related fault codes

F01View →F06View →

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