Unknown
L4 Or F4 on Ideal CLASSIC2

Ideal CLASSIC2 fault code L4 Or F4

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

What the manual says

Manufacturer manual

Flow Thermistor Fault

From this model's manual
Verified against the Ideal/Ideal Idealie Qsg 236287 Ideal Classic2 Install Guide Pdf installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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All 26 fault codes on the CLASSIC2

Seeing a different code? Every code this model can display, in one place.

DUF[-]F1F2 Or Fn Or LnF3F6F7F8 or L8F8/L8F9F9 or L9F9/L9FAFUL[-]L1L2L5 Or F5L6LCoFSHSLUFuP

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