BoilerFaultCodesYour boiler is receiving electrical power and is ready to operate as normal.
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 there is electricity to the Boiler.
What causes this fault?
This is not a fault but a status indicator showing that the boiler is successfully connected to the mains electricity supply. It confirms that the internal control board is receiving power and the unit is in standby mode, ready to fire up when you turn on your heating or hot water. If the light is on but the boiler isn't heating, the issue likely lies with your external thermostat or a specific internal component rather than the power supply itself.
DIY fix possible
This fault may be fixable without an engineer. Check your manual first.
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A boiler cover plan would cover faults like Mains On (Green Light) — no call-out fees, no surprises.
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Potterton Promax FSB 30HE is discontinued — time for a new one?
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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