BoilerFaultCodesYour boiler has detected that there is not enough water pressure inside the system to operate safely, causing it to shut down to prevent overheating.
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
What causes this fault?
This fault occurs when the boiler's internal sensors detect a lack of water, meaning there isn't enough pressure to safely transfer heat away from the burner. The most common reason is a slow leak somewhere in your radiator system or a component inside the boiler, such as the air vent, letting water escape over time.
This issue often surfaces in autumn when the heating is turned back on after summer, as the change in temperature can cause weakened seals to leak or air pockets to move through the pipes.
DIY fix possible
Check the pressure gauge on the front of the boiler; it should be between 1.0 and 1.5 bar.Locate the external filling loop (usually a silver flexible hose) under or near the boiler.Slowly open both valves on the loop until you hear water entering and the gauge reaches 1.5 bar, then close them tightly.Press the reset button (indicated by a flame with a line through it) to restart the boiler.
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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Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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