High Lockout
E42 on Vokera Condexa Pro

Your boiler has stopped working because one of its internal temperature sensors has developed an electrical fault and is reporting incorrect information.

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

Outlet probe short-circuited

What causes this fault?

This fault occurs when the electrical sensor that measures the water temperature exiting the boiler fails or loses its connection. Over time, heat exposure or moisture can cause the sensor's internal wiring to break down or short-circuit, preventing the boiler from knowing if it is safe to continue heating.

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

E 40View →E 41View →

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