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 water pressure inside your heating system drops below the minimum level required for the boiler to fire up. The most common reasons for this are a leak somewhere in your radiators and pipework, or the fact that you recently bled your radiators and haven't topped the water back up yet.
This fault is more common in autumn and winter when the heating is first turned on, as the increased pressure of a hot system can highlight hidden leaks or cause a weakened pressure relief valve to fail.
DIY fix possible
Locate the filling loop (usually a silver braided hose with small valves) underneath the boiler.Slowly open both taps until you hear water flowing and watch the pressure gauge.Close both taps tightly once the needle reaches between 1 and 1.5 bar.
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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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