High
F8 or L8 on Ideal Instinct2 24

Your boiler's internal computer has lost its settings or there is an electrical fault, meaning the system has shut down for safety.

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

Community-sourced, unverified
We could not tie this code to a specific manual. Treat it as indicative only.
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 →L1View →L2View →

All 45 fault codes on the Instinct2 24

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

00CHCH 80F 4 L 4F 5 L 5F 9 L 9F HF LF[-]F1F2F2 or Fn or LnF3F4F5F6F7F8F9F9 or L9FAFnFPFP 1 0FUHH 60L[-]L1L2L4L4 or F4L5L5 or F5L6L8L9LCLnoFPHPH 60UuP

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