High
73 on Alpha E-Tec Plus 28

Your boiler has detected an inconsistent temperature reading between its internal sensors, causing it to shut down for safety.

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

High flow NTC and safety NTC difference detected - The board detects an anomaly in the temperature readings difference between the flow NTC and safety NTC 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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