High Lockout
E 07 on Vokera Hydra

Your boiler has detected a failure within its main control board and has safety-locked itself to prevent incorrect operation.

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

Internal fault (PCB)

What causes this fault?

This fault occurs when the boiler's main control board suffers a hardware failure or a critical memory error, preventing it from processing safety data. The most common reasons are electrical surges, moisture ingress on the circuitry, or simply the natural degradation of electrical components over many years of use.

This fault is slightly more common during winter or periods of heavy rain, as increased system demand and high humidity can put extra stress on aging electrical components.

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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