High
Pulse Red (4 flashes) on Potterton Envoy Plus

Your boiler is trying to start up but is unable to ignite its flame, so it has safely shut down to prevent gas from building up.

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

Continuous - Failed to light

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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Related fault codes

Pulse Red (1 flash)View →Pulse Red (2 flashes)View →

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