BoilerFaultCodesYour boiler has stopped working because the water pressure inside the system has dropped too low 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: Low Water Pressure
What causes this fault?
This fault occurs when the internal water pressure drops below the minimum level required for the boiler to fire up safely. The most common reason is a small leak somewhere in your central heating pipework or radiators, though it can also happen if you have recently bled your radiators and haven't topped the pressure back up.
This fault is frequently seen in autumn when homeowners turn their heating back on for the first time or bleed their radiators to remove air pockets.
DIY fix possible
Locate the filling loop (usually a silver flexible hose) underneath your boiler.Slowly open the one or two taps/handles on the filling loop until you hear water flowing.Watch the pressure gauge and close the taps when the needle reaches between 1 and 1.5 bar.
Find a Gas Safe engineer
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Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like F1 — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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