High
16 on Halstead Dimplex System

Your boiler has stopped working because one of its internal temperature sensors has broken or is sending an incorrect reading, preventing the system from firing up.

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

No ignition. CH Return thermistor failure

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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