BoilerFaultCodesIdeal L6 Fault Code
The Ideal L6 fault code means: your boiler thinks a flame is present even though it hasn't been safely ignited, causing the system to shut down for safety.. It appears on 18 Ideal models in our database.
Technical description: False Flame Lockout
What causes the Ideal L6 fault?
This fault occurs when the boiler's internal sensor detects a flame signal at a point in the starting sequence where there shouldn't be one. The most common reason is a faulty flame sensing electrode that is sending a wrong signal to the control board, or a gas valve that is leaking a tiny amount of gas into the burner area before it is supposed to open.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Ideal models that show the L6 fault code
Click a model for the full fault code list and model-specific repair notes.
- Compact Repair: £120-350
- Compact HE Repair: £100-280
- Concorde Repair: £120-300
- Esprit Repair: £120-£350
- Independent C24 Repair: £120-200
- Logic Code Combi ESP1 Repair: £120-£250
- Logic Combi C24 C30 C35 Repair: £120-£350
- Logic Combi ESP1 Repair: £120-350
- Logic Max & Logic Plus Repair: £120-280
- Logic Max Combi Repair: £120-£250
- Logic Max Plus Repair: £120-280
- Logic Max System Repair: £120-£250
- Logic+ Repair: £120-350
- Logic+ Heat Repair: £120-350
- Logic+ System Repair: £120-280
- Mexico Repair: £120-350
- Sprint Repair: £120-£350
- Vogue Repair: £120-300
Source
Ideal L6 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