BoilerFaultCodesYour boiler is waiting for a signal from your thermostat or timer to turn on, but it isn't receiving one.
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 24V
What causes this fault?
This status occurs when the boiler is powered on and ready to work, but your internal or external heating controls are not telling it to start. The most common reason is that the room thermostat is set too low or the timer is currently in an 'off' period. It can also happen if the batteries in your wireless thermostat have died, breaking the communication link with the boiler.
This is frequently seen after the clocks change or during the first cold spell of autumn when homeowners forget to update their timer settings or replace old thermostat batteries.
DIY fix possible
Check that your room thermostat is turned up higher than the current room temperature.Ensure your programmer or timer is set to 'ON' or 'AUTO'.Replace the batteries in your wireless thermostat if it has any.
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