How much does it cost to fix Heatline error code F.xx?

Typical repair cost for the Heatline F.xx fault is £100-£350 including labour.

F.xx High

Heatline F.xx Fault Code

Q: What does the Heatline F.xx fault code mean?

Your boiler has encountered a specific internal technical error that is preventing it from running safely, and it requires a diagnostic scan by a professional.

Also written as FXX — same fault.

The Heatline F.xx fault code means: your boiler has encountered a specific internal technical error that is preventing it from running safely, and it requires a diagnostic scan by a professional.. It appears on 4 Heatline models in our database.

Technical description: Fault code (specific code depends on the number shown in place of xx), contact a competent person.

Typical repair cost £100-£350 (including labour)

Engineer required

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

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Heatline models that show the F.xx fault code

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

Source

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

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026