High
Earth Fault or Mains Reversal on Potterton Puma 100e

Your boiler has detected an issue with the electrical power supply, meaning it is not receiving electricity in the correct way to operate safely.

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: FLASHING 2 Per Sec, 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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