Emergency
Explosion at burner on Ferroli Pegasus 67 107 2S

Your boiler is struggling to light its flame smoothly, causing a small, audible 'thump' or pop when the gas finally catches. This indicates a combustion issue that requires immediate professional attention to ensure the system is burning safely.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Act immediately

Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now. This fault can be dangerous if ignored.

What the manual says

Manufacturer manual

Delay on ignition. Possible causes: Insufficient gas pressure, boiler shell dirty.

Community-sourced, unverified
We could not tie this code to a specific manual. Treat it as indicative only.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

This is a emergency severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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