How much does it cost to fix Heatline error code F.22?

Typical repair cost for the Heatline F.22 fault is £80-150 including labour.

F.22 High

Heatline F.22 Fault Code

Q: What does the Heatline F.22 fault code mean?

Your boiler has stopped working because the water pressure inside your heating system has dropped too low to operate safely.

Also written as F22 — same fault.

The Heatline F.22 fault code means: your boiler has stopped working because the water pressure inside your heating system has dropped too low to operate safely.. It appears on 4 Heatline models in our database.

Technical description: Low water pressure in the heating installation.

Typical repair cost £80-150 (including labour)

DIY fix possible

Locate the external filling loop (a flexible silver hose with one or two valves) connected to the pipework underneath the boiler.Slowly open the valve(s) to allow mains water into the system while watching the pressure gauge on the front of the boiler.Close the valve(s) tightly once the needle reaches the green zone, typically between 1.0 and 1.5 bar.

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Heatline models that show the F.22 fault code

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

Source

Heatline F.22 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