BoilerFaultCodesWhat the manual says
Manufacturer manualfan pre-run
From this model's manual
Verified against the Glow Worm/Glow Worm Flexicom Cx installation & service manual, page 45.
What causes this fault?
This status occurs when the boiler prepares for ignition by clearing out the combustion chamber. The fan spins up to ensure there is a safe flow of fresh air and to remove any residual gases before the burner light. It is a fundamental part of the boiler's start-up sequence and not a sign of a mechanical failure.
DIY fix possible
This fault may be fixable without an engineer. Check your manual first.
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Related fault codes
All 47 fault codes on the Flexicom cx
Seeing a different code? Every code this model can display, in one place.