Medium
E786 on Navien NCB 35 HE

Your boiler's front cover is not properly attached or secured, which acts as a safety disconnect to prevent the unit from running while it is open.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

Technical description

Improper front panel

DIY fix possible

Switch off the power to the boilerRemove the front cover and ensure no wires are pinchedReplace the front cover, ensuring it is flush and firmly locked in place with all screws tightened

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