High
Earth Fault or Mains Reversal on Potterton Prima 30B

Your boiler is struggling because its electrical connection is wired incorrectly or has a grounding issue, which is preventing it from starting 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

Status: Earth Fault or Mains Reversal. 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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