Low
305 on Worcester Bosch Greenstar 8000 Style GR8700iW 35 SB

Your boiler is temporarily pausing the hot water production to prevent itself from overheating or cycling on and off 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

From this model's manual
Verified against the Worcester Bosch/Worcester Bosch Greenstar 8000 Life System installation & service 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 up to 15 minutes for the anti-cycle timer to expireEnsure hot water taps are fully closedCheck that the hot water temperature setting on the control panel is not set excessively high

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Related fault codes

208View →306View →

All 32 fault codes on the Greenstar 8000 Style GR8700iW 35 SB

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

200201202203204208224227228306306 V815815 B1017 W1022 B1065 B1068 W1075 W1076 W2920 V2927 B2946 V2948 B2950 B2963 B2964 B2965 B2966 B2967 B2970 B2971 B

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