Low
No code on Worcester Bosch Greenstar 35 CDi range

Your boiler is simply going through a self-test cycle after a manual reset and should return to normal operation within a few minutes.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

Reset button pressed by mistake.

Shared across the Greenstar 35 CDi 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.

DIY fix possible

Wait 5-10 minutes for the boiler to complete its internal startup checks.Ensure your thermostat is turned up high enough to call for heat.Check if the display returns to showing a temperature or a blue light.

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All 19 fault codes on the Greenstar 35 CDi range

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

-ll-2 flashes3 flashes4 flashes5 flashes6 flashes7 flashes8 flashes9 flashesA7b1C6d1E2E9EAF7FA

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