High
DRY-FIRE LOCKOUT on Potterton Performa System HE

Your boiler is failing to light because it cannot confirm that water is flowing through the system or that the internal fan is operating correctly.

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 prepurge or Lockout LED flashing 5 times a second

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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