High
L6 on Ideal Independent C24

Your boiler has stopped working because a sensor that measures the temperature of the water flowing out to your radiators is not sending a correct signal.

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

Flow Thermistor

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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Related fault codes

L2View →L5View →

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