Your boiler is receiving power, but it is currently sitting in a standby mode because the control switch is not fully turned to the 'on' position.
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: Electricity supply ON but secondary controls switched OFF and boiler control switch in mid position
What causes this fault?
This status occurs when the boiler has power but the physical control dial is stuck between settings or deliberately set to a standby mode. It essentially means the internal computer is waiting for a clear signal to start, but the switch position is preventing the heating cycle from engaging. Adjusting the dial to the full 'On' position typically resolves this immediately.
DIY fix possible
Locate the main control switch on the boiler's front panel.Ensure the switch is clicked fully to the 'On' or 'Run' position, rather than being stuck in the middle.Check that your external room thermostat or programmer is also set to 'On' or calling for heat.
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