High
Er.8 on Vaillant Turbomax Pro 28 2E

Your boiler's electronic brain is failing to communicate correctly with its internal switches, preventing it from safely starting 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

Switch and control board

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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