High
neon illuminated on Alpha CB 240 / 280

Your boiler has developed an internal electrical fault, meaning the control board is likely failing and unable to safely operate the system.

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

1. Replace neon PCB. 2. check PCB-M11 connector. 3. 20V DC across terminals 49, 52. 4. Replace main PCB.

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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