Medium Lockout
07 on Glow-worm 30ci Plus

Your boiler is struggling to accurately measure the temperature of your hot water due to a faulty internal sensor.

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 hot water temperature has failed or is sending incorrect electrical signals to the main control board. Over time, these sensors can degrade due to constant heat cycles or internal corrosion, meaning the boiler can no longer safely tell how hot the water is. In some cases, the issue may simply be a loose or damaged wire connecting the sensor to the boiler's internal computer.

Engineer required

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

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