Neon l1 High

Ideal Neon l1 Fault Code

Also written as NEONL1 — same fault.

The Ideal Neon l1 fault code means: your boiler has detected that the internal fan or air pressure system is sticking in the 'on' position, preventing it from starting its safety checks.. It appears on 1 Ideal 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: Air pressure switch made
Typical repair cost £120-£280 (including labour)

Engineer required

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

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Ideal models that show the Neon l1 fault code

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

Source

Ideal Neon l1 fault code information on this page is sourced and cross-checked against the official Ideal service / installation manuals for each affected model.

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