Home/Boiler Fault Codes/Ideal L1
IDEAL FAULT CODE
Ideal L1
Indicates low water flow through the boiler, or a hot water flow temperature outside the normal expected range.
WHAT L1 TYPICALLY INDICATES
Indicates low water flow through the boiler, or a hot water flow temperature outside the normal expected range.
WHAT TO DO
This is not a DIY fix — it requires a Gas Safe registered engineer to diagnose and repair safely.
A NOTE ON GAS SAFE REGISTRATION
Any work on the gas side of a boiler in the UK legally requires a Gas Safe registered engineer, it isn't optional. Our engineers are fully Gas Safe registered, and you're always welcome to ask to see ID on the day. This page is general information about what a fault code typically indicates; it is not a substitute for an engineer diagnosing your specific boiler.
Seeing Ideal L1 on your boiler?
Tell us the code and your postcode. A fully Gas Safe registered engineer will diagnose the actual cause before quoting a fix.
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