High
Lockout on Potterton Envoy 30

Your boiler has stopped working for safety reasons because it detected an internal fault and has shut itself down to prevent damage.

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

Control Status: Lockout (Failure to carry out a step or malfunctioning component)

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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