High
75 on Alpha E-Tec Plus 28

Your boiler is struggling to accurately read its own internal water temperatures because its primary thermometers are likely sending conflicting or faulty signals.

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

Return/flow sensor fault - Possible failure of one or both sensors

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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