Low
305 on Worcester Bosch Greenstar CDi Compact

Your boiler is temporarily pausing to prevent damage because it has been switching on and off too frequently for your hot water.

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

Anti fast cycle mode for DHW

From this model's manual
Verified against the Worcester Bosch Greenstar Cdi Compact installation & service manual, page 65.
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 10-15 minutes for the anti-cycle countdown to completeEnsure hot water taps are fully closedCheck for dripping taps that may be triggering the boiler

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