High
Reversed Polarity on Potterton Ultra 2 50 DV

Your boiler has detected that the electrical supply is connected back-to-front, which is a common issue often caused by recent electrical work or a faulty wall plug.

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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