BoilerFaultCodesYour boiler has stopped working because the water pressure is too low, and it has shut down to prevent damage.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: The appliance is blocked because of a water deficiency.
What causes this fault?
This fault occurs when the system loses too much water, causing the internal pressure to drop below a safe operating level. The most common reasons are a slow leak somewhere in your radiators or pipework, or a component like the pressure relief valve failing and letting water escape. Without enough water pressure, the boiler cannot circulate heat safely and shuts down to prevent the internal components from overheating.
This fault is frequently seen in autumn when homeowners turn their heating back on for the first time, as the change in temperature can highlight small leaks or air pockets that developed over the summer.
DIY fix possible
Check the pressure gauge on the front of the boiler or under the casing.Locate the external filling loop (usually a silver flexible hose with small taps).Open the taps slowly until the pressure needle reaches between 1.0 and 1.5 bar, then close them tightly.Press the reset button on the boiler control panel.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like F.13 — 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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