Medium Lockout
YELLOW LED Solid on Vokera Compact HE

Your boiler has detected a problem with the temperature sensor that controls your hot water, meaning you likely have no hot water or the temperature is inconsistent.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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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

DHW thermistor fault (see 7.2.5.2)

What causes this fault?

This fault occurs when the sensor responsible for measuring the temperature of your hot water fails or sends an incorrect signal to the main control board. The most common reason is that the internal components of the sensor have worn out over time due to constant heating and cooling, or the electrical connection has become loose or corroded. Because the boiler no longer knows how hot the water is, it shuts down the hot water function as a safety precaution.

Engineer required

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

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Related fault codes

Red LED SolidView →

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