High
Flow return reversed on Ideal Compact HE

Your boiler has detected that the temperature sensors are reading values in the wrong order, suggesting water may be moving the wrong way or a sensor has become loose.

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

Check if the flow thermistor is correctly clipped to pipe. If not, replace 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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