High
Blocking on Potterton Puma 80/100

Your boiler has detected an internal issue with its airflow system or electrical supply, causing it to shut down for safety reasons.

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

Green LED: ON, Red LED: FLASHING 2 Per Sec. Causes: Mains Frequency incorrect or Air Switch Fault > 1 min. or Reset button held in to force a restart.

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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