How much does it cost to fix Heatline error code F86?

Typical repair cost for the Heatline F86 fault is £120-250 including labour.

F86 Medium

Heatline F86 Fault Code

Q: What does the Heatline F86 fault code mean?

Your boiler has detected an issue with the connection to your underfloor heating system, which prevents the boiler from communicating correctly with that circuit.

The Heatline F86 fault code means: your boiler has detected an issue with the connection to your underfloor heating system, which prevents the boiler from communicating correctly with that circuit.. It appears on 8 Heatline models in our database.

Technical description: Underfl oor heating contact fault

Typical repair cost £120-250 (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 F86 fault code

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

Capriz Plus Repair: £120-200
Centurion 25 Repair: £120-200
Compact 24 Repair: £120-200
Compact 30 Repair: £120-200
Monza Repair: £120-250
Solaris Repair: £120-200
Vizo 24 Repair: £120-200
Vizo 28 Repair: £120-200

Source

Heatline F86 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