How much does it cost to fix boiler error code Reverse polarity?

Typical repair cost for the boiler Reverse polarity fault is £90-160 including labour.

Reverse polarity High

Boiler Fault Code Reverse polarity

Also written as REVERSEPOLARITY — same fault.

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed 31 August 2026

Fault code Reverse polarity appears across 1 boiler brand and 4 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.

Most common meaning Your boiler's electrical power supply has been connected backwards, meaning the live and neutral wires are swapped, which prevents the unit from starting safely. (As reported on Ideal British Gas 125 RD2)

Pick your boiler brand for the Reverse polarity fix

Ideal Reverse polarity 4 models

Source

Information for the Reverse polarity fault code is sourced from the official service / installation manual for each model that displays it. Read more about how we source fault codes →

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 31 August 2026