High Lockout
37 on Remeha Quinta Ace 25

Your boiler has detected an internal communication or sensor data error and has shut down to protect itself.

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

Display of failure code (chapter 11)

What causes this fault?

This fault occurs when the boiler's internal computer brain loses contact with its sensors or the control panel display. It is typically caused by a loose connection on the wiring harness or a component failure on the main circuit board that prevents data from being read correctly.

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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