High Lockout
E7 on Remeha Quinta Ace 25

Your boiler has stopped working because it cannot properly measure the temperature of the water coming back into the unit due to a faulty internal sensor.

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

Return sensor shorted or open circuit

What causes this fault?

This fault occurs when the boiler's internal computer loses communication with the sensor that monitors the temperature of the water returning from your radiators. The most common reason is that the sensor has physically failed or developed an electrical short, meaning the boiler can no longer safely determine how much heat to produce. Occasionally, the issue is caused by a loose connection or damaged wiring between the sensor and the main control board.

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

E0View →E1View →

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