High Lockout
05 on Vokera Linea 28

Your boiler has lost its connection with the external remote controller, meaning they are unable to talk to each other to manage your heating.

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

Appliance is connected to the optional remote control (RC05) and there is a communication problem.

What causes this fault?

This fault occurs when the boiler's main internal computer loses its digital handshake with the wall-mounted remote control unit. The most common reason is a loose connection in the wiring between the two devices or a component failure within the remote control unit itself that stops it from sending or receiving signals. Without this vital link, the boiler cannot receive instructions on when to turn the heating on or off.

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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