High
Red LED on only on Potterton Prima 30B

Your boiler has stopped working because it is not receiving the correct electrical signal or has blown an internal fuse required to power its main components.

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

Check external controls/SW LIVE supply or internal fuse/overcurrent fault (Fan or Pump)

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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