High
2952 on Worcester Bosch 1000

Your boiler is having trouble confirming that the burner is lit safely, so it has stopped working to prevent any potential risks.

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

Internal fault when testing ionisation signal

What causes this fault?

Ionization test error

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

227View →2951View →

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