How much does it cost to fix boiler error code Low mains voltage?

Typical repair cost for the boiler Low mains voltage fault is £250-450 including labour.

Low mains voltage High

Boiler Fault Code Low mains voltage

Also written as LOWMAINSVOLTAGE — same fault.

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed 27 April 2026

Fault code Low mains voltage appears across 1 boiler brand and 7 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.

Most common meaning Your boiler is receiving too little electrical power to operate safely, which may be caused by an issue with your home's electricity supply or a failing internal pump. (As reported on Ideal Concorde)

Pick your boiler brand for the Low mains voltage fix

Ideal Low mains voltage 7 models

Source

Information for the Low mains voltage 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 27 April 2026