Medium Lockout
6x on Vokera Easi-Heat 25

Your boiler has detected a fault with the temperature sensor that controls your hot water, meaning your water may not reach the correct temperature or might not heat up at all.

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

Fault codes 6x appear if a problem exists with the secondary (DHW) thermistor.

What causes this fault?

This fault occurs when the internal sensor responsible for monitoring hot water temperature starts sending incorrect readings or stops communicating with the main control board. The most common reason is that the sensor has suffered from electrical failure or internal corrosion over time, preventing the boiler from knowing how hot the water actually is. As a safety precaution, the boiler stops heating the water to prevent it from becoming dangerously hot.

Engineer required

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

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Related fault codes

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