BoilerFaultCodesYour boiler is taking a brief programmed break to prevent it from turning on and off too quickly while heating your hot water.
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: DHW anti-cycling time. The anti-cycling time for domestic hot water mode is activated.
What causes this fault?
This status occurs because the boiler has reached its target temperature and needs to pause briefly before firing up again. It is a protective measure designed to prevent the burner from turning on and off too frequently, which protects internal components from unnecessary wear and tear. Once the brief cooling period ends or the water temperature drops slightly, the boiler will resume normal operation automatically.
DIY fix possible
Wait 10-15 minutes for the countdown to end naturallyCheck that hot water taps are fully closedEnsure there are no dripping taps in the house
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A boiler cover plan would cover faults like S.28 — no call-out fees, no surprises.
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