High
Spark at ignition electrodes on Alpha CD28

Your boiler is attempting to light but is struggling to complete the ignition process, preventing your heating or hot water from working 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

Follow section 'F' fault finding

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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