High Lockout
RED LED Solid on Vokera Compact HE

Your boiler has detected a fault with its internal temperature sensor, preventing it from heating your water and radiators safely.

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 NTC open/short circuit

What causes this fault?

This fault occurs when the boiler's main temperature sensor, which monitors the heat of the water inside the unit, fails or loses connection. The most common reason is that the internal component has simply worn out over time or a wire has come loose, meaning the boiler can no longer safely regulate its own temperature.

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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