High
F.00 on Glow-worm Energy7 12s-A

Your boiler has temporarily stopped working because it has lost the signal from one of its internal temperature sensors.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

What the manual says

Manufacturer manual

Fault: Flow temperature sensor - NTC plug not plugged in or has come loose, multiple plug on the PCB not plugged in correctly, interruption in cable harness, NTC sensor defective

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 high 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.01View →F.10View →F.11View →

All 41 fault codes on the Energy7 12s-A

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

F.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.76F.77F.78F.83F.84F.85F.86F.87F.88F.89F.91F.97

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