Low
S.20 on Glow-worm Flexicom 24c / 28c

This code is not a fault at all; it simply indicates that your boiler is currently working correctly to provide you with hot water.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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

The domestic hot water demand is activated.

From this model's manual
Verified against the Glow Worm Flexicom 24c 28c installation & service manual, page 46.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

No action is required.This is a status message confirming your boiler is operating normally when a hot tap is turned on.

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