High
F8 or L8 on Ideal CLASSIC2 24

Your boiler has stopped working because its main computer control board is either improperly set up or has suffered an electrical fault.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

What the manual says

Manufacturer manual

PCB UNCONFIGURED/FAULTY OR GAS VALVE SHORT CIRCUIT. SEE SECTION 3.14 IF FAULT PERSISTS REPLACE PCB

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 is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

F1View →F2View →F3View →F4View →F5View →F6View →F7View →F9View →

All 30 fault codes on the CLASSIC2 24

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

F1F2F2 Or Fn Or LnF3F4F5F6F7F8F8/L8F9F9 or L9F9/L9FAFNFUL 2L CL1L2L4L4 Or F4L5L5 Or F5L6L8L9LCLN

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