How much does it cost to fix Johnson Starley error code F15?

Typical repair cost for the Johnson Starley F15 fault is £120-350 including labour.

F15 High

Johnson Starley F15 Fault Code

Q: What does the Johnson Starley F15 fault code mean?

Your boiler has stopped working because it has been manually reset too many times in a short window, suggesting an underlying fault that needs professional attention.

The Johnson Starley F15 fault code means: your boiler has stopped working because it has been manually reset too many times in a short window, suggesting an underlying fault that needs professional attention.. It appears on 1 Johnson Starley model in our database.

Technical description: Reset occurs 5 times within 15 minutes

Typical repair cost £120-350 (including labour)

Engineer required

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

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Johnson Starley models that show the F15 fault code

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

J32 System ET Repair: £120-350

Source

Johnson Starley F15 fault code information on this page is sourced and cross-checked against the official Johnson Starley service / installation manuals for each affected model.

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