High
Er.16 on Vaillant Turbomax Pro 28 2E

Your boiler is struggling to detect the flow of water needed to provide hot water to your taps, usually due to a faulty sensor or internal blockage.

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

DHW 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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