High
b24 on Johnson Starley C16u

Your boiler's main internal computer is having trouble talking to the screen on the front, meaning the controls might not respond correctly.

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

Communication error between PCB and display panel

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

b25View →b26View →

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