High
Reversed Polarity on Potterton Ultra 2 30 DV

Your boiler has detected that the electrical supply wires have been connected in the wrong order, which means it cannot safely operate until the wiring is corrected.

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

Indicator lamp 'Off' - aids electrical commissioning. If 'On', indicates wiring error.

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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