Low
-ll- on Worcester Bosch Greenstar 35 CDi range

Your boiler is performing a routine self-check and filling its internal safety drainage system after the power was turned off and back on.

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

The boiler runs for 15 minutes at minimum heating output to fill the condensate trap. This occurs every time the mains supply has been interrupted.

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 15 minutes for the cycle to complete automaticallyEnsure the boiler power remains switched onThe boiler will return to normal operation once the countdown finishes

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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.

2 flashes3 flashes4 flashes5 flashes6 flashes7 flashes8 flashes9 flashesA7b1C6d1E2E9EAF7FANo code

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