High Lockout
E19 on Vokera Condexa Pro

Your boiler has shut itself down as a safety precaution because it has detected an internal fault that could lead to overheating or unsafe 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

The safety devices have been activated (lockout)

What causes this fault?

This fault occurs when the boiler's internal safety sensors detect that the water temperature has exceeded safe limits or that a critical component has failed. It is usually triggered by a circulation issue within the unit or a faulty sensor sending incorrect data to the control board. For safety, the system shuts down completely to prevent thermal damage to the heat exchanger.

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.

Find a Gas Safe engineer
Search the official register →

Related fault codes

E02View →E03View →E20View →

Related guides you might find useful

Boiler keeps cutting out

Lockout fault with a reset-needed pattern.

Read →

Boiler won't turn on — 9-step checklist

Work through these before the call-out.

Read →

Yellow or orange flame — CO safety

Safety-critical — turn off, read this.

Read →