High
F.72 on Vaillant ecoFIT Pure 825

Your boiler is having trouble comparing temperature readings from different parts of the system, so it has stopped heating to prevent damage.

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/return temperature sensor deviation 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.22View →F.73View →F.74View →

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