High
F.71 on Vaillant ecoTEC plus System

Your boiler is struggling because a temperature sensor is sending inconsistent signals, causing it to block its own operation to play it safe.

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

Flow temperature sensor constant value fault

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

F.72View →F.73View →F.74View →

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