Low Information
305 on Worcester Bosch GB162

Your boiler is currently focused on providing hot water to your taps and will return to heating your radiators once you turn the hot water off.

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.

Technical description

The boiler is waiting for domestic hot water (DHW) operation to end

What causes this fault?

This code appears when the boiler detects a continuous demand for hot water, which takes priority over warming your radiators. The most common reason is simply that a hot tap or shower is currently running, but it can also be triggered if a sensor incorrectly thinks water is flowing or if a valve has become stuck in the hot water position.

DIY fix possible

Check that all hot water taps and showers are fully turned offEnsure there are no dripping taps or leaking hot water pipesWait a few minutes to see if the code clears once the hot water demand stops

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