BoilerFaultCodesZanussi L6 Fault Code
The Zanussi 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 1 Zanussi model in our database.
Technical description: False Flame Lockout
What causes the Zanussi 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 →Avoid the next call-out bill
A cover plan would handle faults like L6: no call-out fees, no surprise bills.
Affiliate links. We may earn a commission at no extra cost to you.
Zanussi models that show the L6 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Zanussi L6 fault code information on this page is sourced and cross-checked against the official Zanussi service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026