BoilerFaultCodesYour boiler is working normally and is currently heating up water for your taps or your radiators.
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: Indicates the appliance is running/operational (typically during hot water demand).
What causes this fault?
This is not a fault, but rather a positive status indicator showing that the boiler is actively burning gas to generate heat. It appears when you turn on a hot tap or when your thermostat signals that the house needs warming up. Once the demand for heat or hot water is met, this light will typically turn off as the boiler enters standby mode.
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.
Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like Green 'Running' light — no call-out fees, no surprises.
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