High
E42 on Biasi Rinnova Adaptive Combi

Your boiler is having trouble breathing or receiving gas, meaning it cannot safely light the flame to provide heating or hot water.

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.

Technical description

Gas supply line / Flue pipes / Fan / Air restrictor

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

E01View →E02View →

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