High
Flow Thermistor on Baxi 130 HE (range)

Your boiler has detected an issue with the sensor that monitors the temperature of the water leaving the unit, meaning it cannot heat your home or water safely.

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

Indicator: Upper LED Off, Middle LED On, Lower LED Flash, Bottom LED On. Fault in flow thermistor 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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