High
E39 on Remeha Avanta 28c

Your boiler has detected an external safety signal, such as a cold protection device or an add-on safety switch, that is preventing it from firing up.

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

Interlock input triggered (e.g. frost protection or external limit)

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

E04View →E06View →

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