High Lockout
07 on Vokera Linea Max

Your boiler has lost its ability to measure the temperature of the water leaving the unit, usually due to a faulty internal sensor or a loose wire.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Primary thermistor fault (Over-temperature sensed by primary sensor)

What causes this fault?

This fault occurs when the boiler's internal computer loses communication with the sensor that monitors the temperature of the water being sent to your radiators. The most common reason is that the sensor has physically failed due to age or internal wear, though it can also be caused by a loose electrical plug or a broken wire within the boiler.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

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