High Lockout
FC on Worcester Bosch Greenstar 30HE

Your boiler's main control board is having trouble communicating with the display panel, meaning the system cannot correctly send or receive instructions.

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

Text display not detected.

What causes this fault?

This fault occurs when the boiler's internal computer can no longer talk to the front display panel. It is usually caused by a loose connection in the internal wiring or a component failure on one of the circuit boards, preventing the boiler from receiving your heating instructions. Over time, heat and vibration inside the unit can also cause these electronic connections to degrade.

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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