High
neon flashing (Section H & K) on Potterton Performa System HE

Your boiler is failing to light the burner because it cannot detect or create the initial spark, so it has safely shut itself down to prevent a build-up of unburnt gas.

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.

What the manual says

Manufacturer manual

Spark at ignition electrodes - Ignition electrode and lead, electrode gap and position, or On/Off/Reset selector fault.

From this model's manual
Verified against the Potterton Boiler Performa System He installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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Boiler cover options

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A cover plan would handle faults like neon flashing (Section H & K): no call-out fees, no surprise bills.

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