BoilerFaultCodesWhat the manual says
Manufacturer manualAnti cycling mode (warm start)
What causes this fault?
This status occurs when the boiler has reached its target temperature and shuts the burner off to prevent overheating. It enters a programmed pause to stop the system from 'short cycling,' which is when the unit rapidly switches on and off. This delay allows the water in your radiators to cool slightly before the boiler fires up again, reducing unnecessary wear and tear.
This is more common during autumn and spring when the weather is milder and your home requires less heat to stay warm.
DIY fix possible
Wait approximately 10 to 15 minutes for the timer to count down naturallyCheck that your room thermostat is turned up high enough to call for heatEnsure your radiator valves are open to allow heat to dissipate
Avoid the next call-out bill
A cover plan would handle faults like S.28: no call-out fees, no surprise bills.
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