How much does it cost to fix Heatline error code 50 Flashing?

Typical repair cost for the Heatline 50 Flashing fault is £120-220 including labour.

50 Flashing High

Heatline 50 Flashing Fault Code

Q: What does the Heatline 50 Flashing fault code mean?

Your boiler is struggling to clear exhaust gases safely, so it has stopped working to prevent any risk of fumes entering your home.

Also written as 50FLASHING — same fault.

The Heatline 50 Flashing fault code means: your boiler is struggling to clear exhaust gases safely, so it has stopped working to prevent any risk of fumes entering your home.. It appears on 2 Heatline models in our database.

Technical description: Fault on Air Pressure Switch

Typical repair cost £120-220 (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 50 Flashing fault code

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

Source

Heatline 50 Flashing 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