BoilerFaultCodesGlow-worm S.08 Fault Code
Also written as S08 — same fault.
The Glow-worm S.08 fault code means: your boiler is taking a short, planned break to prevent the system from turning on and off too frequently, which protects the internal components and saves energy.. It appears on 32 Glow-worm models in our database.
Technical description: Anti cycling period
What causes the Glow-worm S.08 fault?
This status occurs when the boiler has reached its target temperature and needs to pause briefly to prevent the burner from clicking on and off too quickly. It is usually triggered because the heat has nowhere to go, such as when your radiators are already hot or the room thermostat has almost reached its setting. By waiting a few minutes before firing up again, the boiler reduces unnecessary wear on the components and operates more efficiently.
This is more common during autumn and spring when the weather is milder and your home doesn't require the boiler to run at full power for long periods.
DIY fix possible
Wait for 10 to 15 minutes as this is a normal operating status and not a faultEnsure your room thermostat is turned up to your desired temperatureCheck that your radiator valves are open to allow the heat to dissipate
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Glow-worm models that show the S.08 fault code
Click a model for the full fault code list and model-specific repair notes.
- 30cxi
- 38cxi
- Betacom2 28
- Betacom4
- Easicom 24
- EASICOM 3 25r
- Easicom3 Combi
- Easicom3 System
- Energy
- Energy 35 Store
- Energy Regular
- Energy System
- Energy2 30c
- Energy7 Combi
- Energy7 Regular
- Energy7 System
- Essential
- Flexicom 18sx
- Flexicom 24c / 28c
- Flexicom cx
- Flexicom hx
- Flexicom sx
- Sustain 12s
- Ultimate 3 25R
- Ultimate3 Combi
- Ultimate3 System
- Ultracom 2 CXI
- Ultracom 2 SXI
- Ultracom 24cx 30cx
- Ultracom 35 Store
- Ultracom cxi
- Ultracom sxi
Source
Glow-worm S.08 fault code information on this page is sourced and cross-checked against the official Glow-worm service / installation manuals for each affected model.
- Glow-worm Ultracom 2 CXI manual (PDF)
- Glow-worm Betacom2 28 manual (PDF)
- Glow-worm Betacom4 manual (PDF)
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 31 August 2026