F8 High

Zanussi F8 Fault Code

The Zanussi F8 fault code means: your boiler's computer brain has lost its settings or is experiencing an electrical fault, preventing the system from starting up.. It appears on 1 Zanussi model in our database.

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.

Technical description: PCB UNCONFIGURED/FAULTY OR GAS VALVE SHORT CIRCUIT. SEE SECTION 3.19 IF FAULT PERSISTS REPLACE PCB

What causes the Zanussi F8 fault?

This fault occurs when the boiler's main control board loses its identity or suffers an internal electrical failure, meaning it no longer knows how to safely manage the heating process. It can also be triggered by a faulty gas valve or damaged wiring creating a short circuit that prevents the system from starting. Essentially, the 'brain' of the boiler has become corrupted or disconnected from the components it needs to control.

Typical repair cost £250-£550 (including labour)

Engineer required

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

Find a Gas Safe engineer

Search the official register for a qualified engineer in your area.

Gas Safe Register →

Avoid the next call-out bill

A cover plan would handle faults like F8: no call-out fees, no surprise bills.

Approved partner
Domestic Appliance Guard
Unlimited call-outs, 24/7 helpline, no price-hike promise
Get a quote →

Affiliate links. We may earn a commission at no extra cost to you.

Zanussi models that show the F8 fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Zanussi F8 fault code information on this page is sourced and cross-checked against the official Zanussi service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026