High Lockout
Test 1A on Vokera Pinnacle

Your boiler has lost its display and controls, which usually means the main internal circuit board has failed while the pump is stuck in a backup safety mode.

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

No display, pump running

What causes this fault?

This issue occurs when the boiler's central brain, the printed circuit board, suffers a critical electronics failure or loses power entirely. It is usually caused by an internal electrical short or a worn-out component on the board that prevents it from communicating with the display. Because the control board can no longer manage the system, the pump stays running as a built-in safety measure to prevent the unit from overheating.

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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