How much does it cost to fix Ideal error code L-?

Typical repair cost for the Ideal L- fault is £0-350 including labour.

L- High

Ideal L- Fault Code

Q: What does the Ideal L- fault code mean?

Your boiler has switched itself off for safety and is displaying a 'lockout' status, which will be accompanied by a second flashing code to tell you exactly what is wrong.

Also written as L — same fault.

The Ideal L- fault code means: your boiler has switched itself off for safety and is displaying a 'lockout' status, which will be accompanied by a second flashing code to tell you exactly what is wrong.. It appears on 3 Ideal models in our database.

Technical description: Boiler is in lockout for a specific error. Display will be blinking, alternating with a number or letter to show which error is detected.

Typical repair cost £0-350 (including labour)

DIY fix possible

Check the display for the secondary flashing number or letter that follows the 'L'Press and hold the 'Reset' button for two secondsCheck if your gas credit has run out or if other gas appliances are working

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Ideal models that show the L- fault code

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

Source

Ideal L- 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