Low
S.99 on Glow-worm Easicom3 System

Your boiler is currently performing an automatic top-up of the system water pressure to ensure it has enough water to function correctly.

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

Automaticfillingactive

From this model's manual
Verified against the Glow Worm Easicom3 System installation & service manual, page 42.
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

Wait for a few minutes while the boiler completes the automatic filling process.Do not turn off or reset the boiler while this status code is displayed.If the code persists for more than an hour, check your central heating pressure gauge to ensure it is not rising above 2.0 bar.

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