High
73 on Alpha Intec2 25 28XE

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

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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