Low
305 0 on Worcester Bosch Greenstar 30i

Your boiler is temporarily pausing the hot water production to prevent itself from overheating or cycling too frequently.

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

Boiler in hot water anti-cycle mode

Shared across the 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 10 to 15 minutes for the anti-cycle timer to expire naturallyEnsure your hot water taps are fully turned offCheck that the boiler pressure gauge is within the green zone (usually 1 to 1.5 bar)

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