Emergency
Earth Fault or Mains Reversal on Potterton Suprima HE

Your boiler has detected an electrical safety issue, likely caused by a wiring problem where the power connection is either incorrectly configured or not properly grounded.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Act immediately

Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now. This fault can be dangerous if ignored.

Technical description

Status: Earth Fault or Mains Reversal. Green LED: FLASHING 2 Per Sec. Red LED: FLASHING 2 Per Sec.

Engineer required

This is a emergency severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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