High
E42 on Ravenheat RSF 82E

Your boiler has detected an unusual temperature difference between the water sending heat out and the water returning, which usually indicates a circulation problem.

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

Different temperature error

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

E41View →E43View →E05View →

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