High
30 - 40 on Chaffoteaux Minima MX2 24FF / 30FF

Your boiler has detected a faulty internal temperature sensor that monitors the water returning from your radiators, which prevents the system from heating effectively.

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

Central heating return thermistor faulty (open circuit)

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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