Your boiler is in an automatic mode where it is adjusting the temperature of your radiators to heat your home more efficiently.
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: SARA function active
What causes this fault?
This is actually a normal operation signal rather than a malfunction, occurring when the boiler's automatic temperature control system is engaged. It physically indicates that the control board is modulating the water temperature based on the demand from your thermostat to ensure the system runs as efficiently as possible. You may see this when the boiler is working hard to reach your set temperature or when it is fine-tuning the heat output during a long heating cycle.
This status is most frequently seen during autumn and winter when the central heating is used regularly and the system is under constant demand.
DIY fix possible
No action is required as this is a normal operating function, not a fault.If you wish to stop this mode, turn the heating temperature selector dial slightly.The light will stop flashing once the boiler finishes its adjustment period.
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