High
Return Thermistor on Baxi 130 HE (range)

Your boiler has detected a problem with the sensor that monitors the water temperature coming back into the unit, causing it to stop running for safety.

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 Flash, Middle LED On, Lower LED On, Bottom LED Off. Fault in return 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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