neon flashing (4th instance) High

Potterton neon flashing (4th instance) Fault Code

Also written as NEONFLASHING4THINSTANCE — same fault.

The Potterton neon flashing (4th instance) fault code means: your boiler is trying to start the fire needed to heat your water but is failing to detect a flame after several attempts.. It appears on 1 Potterton model in our database.

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: Spark at ignition electrodes for up to 10 seconds but no flame. Change main PCB or go to sections H and K.
Typical repair cost £180-350 (including labour)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Potterton models that show the neon flashing (4th instance) fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Potterton neon flashing (4th instance) fault code information on this page is sourced and cross-checked against the official Potterton service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026