BoilerFaultCodesWhat the manual says
Manufacturer manualfan pre-run
Shared across the range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s manual.
What causes this fault?
This is not actually a fault, but rather a normal part of the boiler's starting routine where the fan spins up to clear the combustion chamber. It occurs every time there is a demand for heating or hot water to ensure the system is safe to ignite. If the code stays on the screen for a long time without the boiler firing up, it may indicate that the fan is struggling to reach the required speed.
DIY fix possible
This fault may be fixable without an engineer. Check your manual first.
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Related fault codes
All 52 fault codes on the Flexicom hx
Seeing a different code? Every code this model can display, in one place.