Your boiler is working fine but hasn't started the heating because your external thermostat or timer is currently telling it to stay off.
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: No Heating demand from external controls 230V
What causes this fault?
This status code occurs because the boiler's internal computer is waiting for a signal from your wall thermostat or timer before it begins heating your radiators. The most common reason is simply that the room temperature is already higher than the setting on your thermostat, or your heating schedule is currently set to an 'off' period. It can also be caused by flat batteries in a wireless thermostat preventing the 'switch on' signal from reaching the boiler.
This code is frequently seen during the transition into autumn, when homeowners first try to turn their heating on only to find their thermostat batteries have died over the summer.
DIY fix possible
Check that your room thermostat is turned up higher than the current room temperature.Ensure your programmer or central heating timer is set to 'On' or 'Auto'.Replace the batteries in your wireless wall thermostat if the screen is blank or showing a low battery symbol.
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