BoilerFaultCodesYour boiler is working normally and is currently firing to heat your radiators or 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: This indicates that the Burner has fired up and is heating your system.
What causes this fault?
This is a normal operational status and not a mechanical failure. It occurs because the boiler’s internal controls have detected a demand for heat and have successfully ignited the burner to warm the water. Once your home reaches the desired temperature, this light will eventually turn off as the boiler enters standby mode.
You will see this more frequently during the winter months when your central heating is running for longer periods to keep your home warm.
DIY fix possible
This fault may be fixable without an engineer. Check your manual first.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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A boiler cover plan would cover faults like Burner On (Green Light) — no call-out fees, no surprises.
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Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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