FN
FAULT CODE
Ideal
Flame Loss (Alternative Code)
Medium Severity
DIY Check Possible
On some Ideal models, FN is displayed alongside or instead of F2 to indicate flame loss during operation.
Cold Weather Note
FN in winter is commonly a frozen condensate pipe.
Step-by-Step Fix Guide
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Step 1
Check gas supply
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Step 2
In cold weather, check the condensate pipe for freezing
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Step 3
Reset the boiler once
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Step 4
If FN persists, call a Gas Safe engineer
Gas Safe Reminder
Work on gas appliances must be carried out by a Gas Safe registered engineer. The steps above cover safe checks a homeowner can perform - any internal component replacement requires a qualified professional. If in doubt, always call an engineer.