High
16 on Halstead Netaheat 10/16E

Your boiler is failing to start because it cannot accurately read the temperature of the water circulating back into it.

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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