High
t1 on Worcester Bosch Greenstar 28CDi

Your boiler is currently trying to light its internal flame but is struggling to ignite successfully.

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.

What the manual says

Manufacturer manual

Igniter test. The igniter will spark for a maximum of 30 seconds. The spark will be audible if the igniter is OK.

From this model's manual
Verified against the Worcester Bosch Greenstar 28cdi Compact installation & service manual, page 71.
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 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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