High Lockout
30 on Vokera Synergy E

Your boiler has detected an internal communication failure between its electronic control boards and has shut down for safety.

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

Fault code 30 shows (from Fault Finding Test B)

What causes this fault?

This fault occurs when the boiler's internal computers stop talking to each other, preventing the system from following safe operating instructions. The most common reason is a physical breakdown of the electronic components on the main control board or a loose connection in the wiring that links the display to the engine. Because the boiler cannot confirm its settings are correct, it shuts down completely as a protective measure.

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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