High
Blocking on Potterton Prima 30B

Your boiler has detected an issue with the air supply or internal startup signal, causing it to lock itself out 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

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

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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