Low
S.02 on Glow-worm Sustain 12s

Your boiler is currently preparing to heat your home by circulating water through the pipes before the main burner ignites.

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

Heating mode: Pump pre-run

From this model's manual
Verified against the Glow Worm Sustain 12s installation & service manual, page 32.
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 5-10 minutes as this is a normal operational status.Ensure your room thermostat is calling for heat.If the code persists for more than 15 minutes, restart your boiler using the reset button.

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