Low
S.30 on Glow-worm Flexicom cx

Your boiler is working fine, but it is waiting for a signal from your thermostat or programmer to tell it to turn the heating on.

Monitor it

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.

What the manual says

Manufacturer manual

No Heating demand from external controls 230V

From this model's manual
Verified against the Glow Worm Flexicom Cx installation & service manual, page 45.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

What causes this fault?

This status occurs when the boiler is powered on and ready to work but hasn't received an electrical signal from your thermostat to start heating the radiators. The most common reason is simply that the room temperature is already higher than the setting on your dial, or the timer is currently in an 'off' period. It can also happen if the batteries in your wireless thermostat have died, preventing the signal from reaching the boiler.

This is very common in autumn when homeowners first try to turn their heating on only to find their thermostat batteries have drained over the summer.

DIY fix possible

Check that your room thermostat is turned up higher than the current room temperature.Ensure your heating programmer or 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 icon.

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