High Lockout
3 7. on Remeha Quinta Ace 25

Your boiler has stopped working because it cannot correctly measure 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

Temp.sensor fault: Return temperature sensor defective or not connected.

What causes this fault?

This fault occurs when the boiler's internal computer loses communication with the sensor that monitors water coming back from your radiators. The most common reason is that the sensor has physically failed due to age or internal wear, though it can also be triggered by a loose or damaged connection in the internal wiring.

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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