Low
S.04 on Glow-worm Flexicom hx

Your boiler is operating normally and is currently heating up to provide warmth for your radiators or hot water.

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

burner on

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 is actually not a fault, but a normal status message indicating that the boiler identifies a need for heat. It shows that the internal burner has successfully ignited and is now burning gas to heat the water for your central heating or hot water cylinder. You may see this code frequently during the winter months as the system works to keep your home at the desired temperature.

DIY fix possible

No action is required as this is an advisory status code rather than a fault.Check your thermostat or programmer to ensure the heating is scheduled to be on.Wait for the boiler to finish its heating cycle, at which point the code will change.

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