BoilerFaultCodesYour boiler is receiving power and is currently switched on at the mains supply.
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: Mains electricity ON
What causes this fault?
This is not actually a fault, but rather a status indicator showing that your boiler is connected to a live electrical supply and ready to operate. It appears when the power is turned on at the fused spur or control switch, confirming that the internal circuit board is receiving electricity. If your heating isn't working while this is displayed, the issue likely lies with your external thermostat or timer settings rather than the boiler itself.
DIY fix possible
No action is required as this is a status indicator rather than a fault.If the boiler is not firing despite this light being on, check that your room thermostat is turned up.Ensure any external timers or programmers are set to 'On' or 'Auto'.
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