High
1 (Group 1) on Worcester Bosch Greenstar Ri

Your boiler is trying to start up and even lighting the gas, but it fails to recognise that the flame has actually caught, so it safely shuts down again.

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

No ionisation detection after ignition

Shared across the Greenstar range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s manual.
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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Related fault codes

EAView →D1View →227View →

All 15 fault codes on the Greenstar Ri

Seeing a different code? Every code this model can display, in one place.

2 (Group 1)3 (Group 1)4 (Group 1)5 (Group 1)6789101112131415

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