High
Pulse Red (6 flashes) on Potterton Envoy Plus

Your boiler is failing to detect the airflow needed for safe operation, so it has shut down to prevent it from firing up improperly.

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 - Air Pressure Switch Fault

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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