BoilerFaultCodesYour boiler is receiving power and is operating normally; this is a status indicator rather than a fault.
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: Appiance On lamp
What causes this fault?
The letter 'A' appears on the display simply to show that the boiler is switched on and receiving electrical power. It is a status symbol rather than a malfunction, indicating that the internal control board is ready to respond to a request for heating or hot water. You will see this during normal operation when the boiler is in standby mode.
DIY fix possible
No action is required as this indicates the appliance is turned on and functioning.Ensure your thermostat is set to a temperature higher than the current room temperature if you want the heating to start.Check that your timer or programmer is set to 'On' or 'Auto'.
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A boiler cover plan would cover faults like A — no call-out fees, no surprises.
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