High
Er.6 on Vaillant Turbomax Pro 28 2E

Your boiler has detected that the water temperature is rising too quickly or overheating, suggesting that internal parts are struggling to move heat away from the burner efficiently.

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

Main heat exchanger

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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