BoilerFaultCodesYour boiler is working normally and simply indicating that your central heating is currently switched on and heating your home.
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: Illuminates whenever there is a demand for central heating i.e. the radiator temperature control is turned on and the external heating controls are calling for heat.
What causes this fault?
This indicator is triggered when your thermostat or timer tells the boiler that your home needs warming up. It signifies that the internal pump has started and the burner is firing to send hot water to your radiators. It is a sign of healthy operation rather than a breakdown.
This light is most frequently seen during autumn and winter when the central heating is used daily to combat colder outdoor temperatures.
DIY fix possible
Check your room thermostat is set to the desired temperatureEnsure your heating programmer is set to 'on' or 'auto'Wait for the radiators to reach the temperature set on the boiler dial
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like Central heating demand indicator (yellow) — no call-out fees, no surprises.
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