What does the Glow-worm F22 fault code mean?

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

How much does it cost to fix Glow-worm error code F22?

Typical repair cost for the Glow-worm F22 fault is £80-150 including labour.

Locate the filling loop (a flexible silver hose connecting two pipes near the bottom of the boiler).

Manufacturer manual

Low water pressure or no water in the system

Shared across the Flexicom 24c / 28c range

This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s manual.

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

Boiler cover options

A cover plan would handle faults like F22: no call-out fees, no surprise bills.

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Seeing a different code? Every code this model can display, in one place.

Six most common causes of dropping pressure.

1 to 1.5 bar when cold on most UK boilers, from the manuals.

Turn it off first. Where the water comes from tells you which part has gone.