High Lockout
E83476 on Potterton Powermax HE

Your boiler is struggling to spark or maintain a flame because the high-voltage internal ignition cable has developed a fault.

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

HT Lead

What causes this fault?

This fault occurs when the high-voltage cable that creates the spark becomes degraded or develops a hairline crack in its insulation. When this happens, the electrical current leaks away before it can reach the burner, meaning the boiler cannot ignite the gas safely. The most common reason is simple wear and tear from the extreme heat inside the boiler casing over several years.

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 →E02View →A01View →

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