High Lockout
E09 on Remeha Quinta 30

Your boiler has stopped working because it cannot communicate with the sensor that monitors the temperature of the water returning to the unit.

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

Interruption return sensor: check wiring and sensor.

What causes this fault?

This fault occurs when the boiler's main control board loses the electrical signal from the sensor that monitors the temperature of the water coming back from your radiators. The most common reason is that the sensor has developed an internal electrical failure or the wiring connecting it to the brain of the boiler has become loose or damaged.

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

E07View →E08View →E11View →

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