High
E35 on Keston C36p

Your boiler is struggling to detect a steady flow of electricity, which is likely caused by a minor power dip or a faulty electrical connection in your home.

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

Mains supply frequency incorrect - There may be a problem with your power supply.

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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Related fault codes

E01View →E04View →

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