BoilerFaultCodesYour boiler has detected that the water pressure is too low to operate safely, which is usually caused by a small leak or after bleeding your radiators.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Low Water Pressure
What causes this fault?
This fault occurs when the internal sensors detect that there isn't enough water circulating through the system to safely transfer heat. The most common reasons are small leaks from radiator valves or pipework, or simply having recently bled your radiators, which removes pressure alongside the trapped air.
This code is frequently seen in autumn when homeowners turn their heating back on for the first time or bleed their radiators to prepare for winter.
DIY fix possible
Locate the filling loop (the flexible silver hose) underneath the boiler.Slowly open the one or two valves on the hose until you hear water entering the system.Watch the pressure gauge and close the valves tightly once the needle reaches 1.5 bar.
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A boiler cover plan would cover faults like F1 — no call-out fees, no surprises.
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