High
E28 on Main Eco 24 HE

Your boiler's computer module has been identified as incompatible or was recently replaced incorrectly, preventing the system from operating safely.

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

Incorrect PCB Fitted

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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