BoilerFaultCodesYour boiler is temporarily pausing its burner to prevent it from switching on and off too frequently, which protects the internal parts from unnecessary wear.
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: Anti-cycle time
What causes this fault?
This occurs when the boiler reaches its target temperature too quickly, often because your radiators are already warm or the heating system is smaller than the boiler's output. To protect the internal components from burnout caused by constant stopping and starting, the system enforces a short rest period. It is essentially the boiler taking a 'breather' until the water temperature drops enough to start a new, efficient heating cycle.
This is more common during the spring and autumn when the weather is mild and your home requires only a small amount of heat to reach the thermostat setting.
DIY fix possible
Check that all radiator valves (TRVs) are fully open to allow heat to escape the boilerMonitor the boiler for a few minutes as it should restart automatically once the timer expiresEnsure the system pressure is between 1.0 and 1.5 bar on the front gauge
Find a Gas Safe engineer
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A boiler cover plan would cover faults like 2.4 — no call-out fees, no surprises.
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