Low
S.36 on Glow-worm Flexicom hx

Your boiler is working correctly, but it is currently sitting in standby because your thermostat or external timer is not telling it to turn 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 24V

From this model's manual
Verified against the Glow Worm Flexicom 18sx installation & service manual, page 47.
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 because the boiler is waiting for a signal from your external controls to start heating. It usually means your room thermostat is set too low, the programmer is in an 'off' period, or the batteries in your wireless controller have run out. While the boiler is powered and ready to go, the connection from your wall thermostat is currently telling it to stay in standby mode.

This is frequently seen during the transition into autumn when homeowners forget to replace thermostat batteries or update their timer schedules for the colder weather.

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 thermostat if the screen is blank or showing a low battery symbol.

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