Emergency
F.76 on Glow-worm Energy7 12s-A

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.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Act immediately

Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now. This fault can be dangerous if ignored.

What the manual says

Manufacturer manual

The safety cut-out in the primary heat exchanger is defective - Safety cut-out feedback does not match the gas valve assembly feedback

From this model's manual
Verified against the Glow Worm/Glow Worm Energy7 System installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

This is a emergency severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

F.28View →F.29View →F.75View →

All 41 fault codes on the Energy7 12s-A

Seeing a different code? Every code this model can display, in one place.

F.00F.01F.10F.11F.12F.13F.20F.22F.23F.24F.25F.27F.28F.29F.32F.49F.61F.62F.63F.64F.65F.67F.68F.70F.71F.72F.73F.74F.75F.77F.78F.83F.84F.85F.86F.87F.88F.89F.91F.97

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