BoilerFaultCodesYour boiler has stopped working because the water pressure is too low for it to run safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Not enough water in the system
What causes this fault?
This fault occurs when the internal sensors detect that there isn't enough water circulating through the boiler to operate safely. The most common reason is a slow leak somewhere in your radiator system or a failing component that has allowed pressure to drop below the minimum threshold. Without enough water, the boiler shuts down to prevent the heat exchanger from overheating.
This issue is frequently seen in autumn when homeowners turn their heating back on for the first time, as tiny leaks during the summer months can gradually drain the system pressure.
DIY fix possible
Check the pressure gauge on the front of the boiler; it is likely below 1 bar.Locate the external filling loop, which is usually a flexible silver hose under the boiler.Slowly open the tap valves on the hose until the gauge reaches 1.5 bar, then close them tightly.Reset the boiler to clear the fault code.
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A boiler cover plan would cover faults like F22 — no call-out fees, no surprises.
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