BoilerFaultCodesYour 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.
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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A boiler cover plan would cover faults like 305 — no call-out fees, no surprises.
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Worcester Bosch GB162 is discontinued — time for a new one?
Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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