BoilerFaultCodesGlow-worm F.76 Fault Code
Also written as F76 — same fault.
The Glow-worm F.76 fault code means: your boiler has detected a safety disagreement between its internal temperature protection device and the gas control system, so it has safely shut down to prevent any risk.. It appears on 13 Glow-worm models in our database.
Technical description: The safety cut-out in the primary heat exchanger is defective - Safety cut-out feedback does not match the gas valve assembly feedback
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Glow-worm models that show the F.76 fault code
Click a model for the full fault code list and model-specific repair notes.
- Compact Repair: £120-250
- Energy Repair: £180-350
- Energy System Repair: £250-450
- Energy2 30c Repair: £150-350
- Energy7 Combi Repair: £150-300
- Energy7 System Repair: £180-350
- Flexicom 24c / 28c Repair: £150-300
- MicraCom Repair: £150-300
- Sustain 12s Repair: £180-450
- Sustain 15s Repair: £180-450
- Sustain 18s Repair: £180-450
- SUSTAIN 30c Repair: £180-350
- SUSTAIN 35c Repair: £180-350
Source
Glow-worm F.76 fault code information on this page is sourced and cross-checked against the official Glow-worm service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 31 August 2026