BoilerFaultCodesYour boiler has detected that there is not enough water pressure inside the system to operate safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Dry fire (No water in boiler)
What causes this fault?
This fault occurs when the boiler's internal sensors detect that the system has lost its water pressure, which is necessary to safely transfer heat. The most common reasons are a slow leak from a radiator valve or pipework, or a failing expansion vessel that can no longer manage the pressure inside the unit.
This fault is frequently seen in autumn when the heating is turned on for the first time after summer, as the change in temperature can highlight small leaks or pressure drops.
DIY fix possible
Locate the filling loop (usually a silver flexible hose) underneath or near the boiler.Slowly open the valve(s) to allow water into the system until the pressure gauge reads between 1.0 and 1.5 bar.Close the valves tightly and press the reset button on the boiler control panel.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like F.22 — no call-out fees, no surprises.
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